How could Rabbi Yehuda respond regarding the complete Torah?

Summary: The famous dispute about the last eight pesukim in the Torah.

Post: Rashi brings down a dispute about the authorship of the last eight pesukim in the Torah.

5. And Moses, the servant of the Lord, died there, in the land of Moab, by the mouth of the Lord.		ה. וַיָּמָת שָׁם מֹשֶׁה עֶבֶד יְ־הֹוָ־ה בְּאֶרֶץ מוֹאָב עַל פִּי יְ־הֹוָ־ה:
And Moses… died there: Is it possible that Moses died, and [then] wrote, “And Moses… died there”? But [the answer is:] Moses wrote up to that juncture, and Joshua wrote from then on. Says Rabbi Meir: But is it possible that the Torah Scroll would be lacking anything at all, and yet Scripture states (Deut. 31:26),“Take this Torah Scroll” [and Moses commanded this to the Levites; so, according to the above opinion, is it possible that the Torah Scroll referred to there was an incomplete one, up to the juncture of Moses’s death? This cannot be!] Rather, [continues Rabbi Meir, we must say that] The Holy One, blessed is He, dictated this [i.e., the verse “And Moses… died there”], and Moses wrote it in tears. — [B.B. 15b, Sifrei 33:34]		וימת שם משה: אפשר משה מת וכתב וימת שם משה, אלא עד כאן כתב משה, מכאן ואילך כתב יהושע. ר' מאיר אומר אפשר ספר התורה חסר כלום, והוא אומר (לעיל לא, כו) לקוח את ספר התורה הזה, אלא הקב"ה אומר ומשה כותב בדמע:

The first position is put forth in the Gemara by Rabbi Yehuda, or possibly Rabbi Nechemia. The Sifrei leaves this attribution out. The second position in our gemara is that of Rabbi Meir. In our Sifrei, Rabbi Shimon. The gemara and Sifrei also appear to be quoting different pesukim, but again, one would need to consult alternate girsaot.

In terms of tone, leaving out the attribution leaves an impression that this was a hava amina which was rejected.  Yet there are other braytot which indicate that Rabbi Yehuda held firm in his position, which state that Yehoshua wrote his sefer as well as eight pesukim in the sefer Torah.

I've seen some who suggest that Rabbi Yehuda somehow agrees with Rabbi Meir about the Torah scroll written by Moshe in 31:25, "Take this Torah scroll", that that sefer Torah was complete. I don't find those explanations convincing, but they are working at the least with the assumption that Rabbi Yehuda has some sort of response.

What are the pesukim which are used as evidence? Well, Rashi cited the pasuk given in the gemara, Devarim 31:26:

26. "Take this Torah scroll and place it along side the ark of covenant of the Lord, your God, and it will be there as a witness.

כו. לָקֹחַ אֵת סֵפֶר הַתּוֹרָה הַזֶּה וְשַׂמְתֶּם אֹתוֹ מִצַּד אֲרוֹן בְּרִית יְ־הֹוָ־ה אֱלֹהֵיכֶם וְהָיָה שָׁם בְּךָ לְעֵד:

The pasuk cited in our Sifrei is Devarim 31:9:

9. Then Moses wrote this Torah, and gave it to the priests, the descendants of Levi, who carried the ark of the covenant of the Lord, and to all the elders of Israel.

ט. וַיִּכְתֹּב מֹשֶׁה אֶת הַתּוֹרָה הַזֹּאת וַיִּתְּנָהּ אֶל הַכֹּהֲנִים בְּנֵי לֵוִי הַנֹּשְׂאִים אֶת אֲרוֹן בְּרִית יְ־הֹוָ־ה וְאֶל כָּל זִקְנֵי יִשְׂרָאֵל:

I suppose either one works.

But at first glance, the proof from the pasuk seems akin to the proof that Yaakov wore a yarmulke. It says Vayeitzei Yaakov. Would Yaakov go anywhere without a yarmulke?!

Similarly, it is great that the pasuk states "And Moshe wrote this Torah" or "Take this Torah scroll". But who says it is a complete Torah scroll? Maybe it refers to writing everything up to but not including the last eight verses! There is simply the rhetorical question of אפשר ספר התורה חסר כלום, והוא אומר (לעיל לא, כו) לקוח את ספר התורה הזה. But why not say that the Torah was indeed missing something?

What the two verses from the gemara and Sifrei have in common, such that one can exchange one for the other, is the word hazeh and hazot. These words are darshened elsewhere to indicate something you can point to. And given that we know our own Torah, it would seem that the derasha here is to this known sefer Torah, namely ours. And that would need to be complete.

If it is a derasha, then perhaps Rabbi Yehuda does not darshen that pasuk, or at least not in that way. On a peshat level, one need not assert that the scroll Moshe wrote and had the Leviim put in the aron was identical to our own, without missing the last eight pesukim written by a different author. And perhaps  the audience of zeh or zot is not us, the reader of the Torah, but rather zeh and zot have local meaning.

Alternatively, it is not based on zot, but on calling it a sefer haTorah. And sefer haTorah has a halachic definition, which is being imposed upon this scroll in Moshe's days.

Another strong possibility, though I am not sure we can read it into the words in the gemara and Sifrei, is that this is all based on a pasuk in context. Thus, if we look at the context of the quote as found in the gemara:

24. And it was, when Moses finished writing the words of this Torah in a scroll, until their very completion,		כד. וַיְהִי כְּכַלּוֹת מֹשֶׁה לִכְתֹּב אֶת דִּבְרֵי הַתּוֹרָה הַזֹּאת עַל סֵפֶר עַד תֻּמָּם:
25. that Moses commanded the Levites, who carried the ark of the covenant of the Lord, saying:		כה. וַיְצַו מֹשֶׁה אֶת הַלְוִיִּם נֹשְׂאֵי אֲרוֹן בְּרִית יְ־הֹוָ־ה לֵאמֹר:
26. "Take this Torah scroll and place it along side the ark of covenant of the Lord, your God, and it will be there as a witness.		כו. לָקֹחַ אֵת סֵפֶר הַתּוֹרָה הַזֶּה וְשַׂמְתֶּם אֹתוֹ מִצַּד אֲרוֹן בְּרִית יְ־הֹוָ־ה אֱלֹהֵיכֶם וְהָיָה שָׁם בְּךָ לְעֵד:

we see that the Torah itself explicitly asserts that Moshe finished writing the words of the Torah, and that these words were until their very completion. A diyuk into these words could well spark Rabbi Meir's rhetorical question. But again, this would be a derasha.

On a peshat level, we are not forced to assume that this Torah which Moshe wrote was word-for-word identical to our own. Aside from this, it is unclear that we need to treat it as an entire sefer Torah. Consider more context, with Rashi's elaboration:

11. When all Israel comes to appear before the Lord, your God, in the place He will choose you shall read this Torah before all Israel, in their ears.		יא. בְּבוֹא כָל יִשְׂרָאֵל לֵרָאוֹת אֶת פְּנֵי יְ־הֹוָ־ה אֱלֹהֶיךָ בַּמָּקוֹם אֲשֶׁר יִבְחָר תִּקְרָא אֶת הַתּוֹרָה הַזֹּאת נֶגֶד כָּל יִשְׂרָאֵל בְּאָזְנֵיהֶם:
you shall read this Torah: The king [of Israel] would read from the beginning of “These are the words…” (Deut. 1:1), as we find in tractate Sotah (41a).		תקרא את התורה הזאת: המלך היה קורא מתחלת אלה הדברים, כדאיתא במסכת סוטה (מא א) על בימה של עץ שהיו עושין בעזרה:

This is, then, just sefer Devarim, which is "missing" Bereishit through the end of Bemidbar. Rashi does  seem to make a distinction between the "Torah" in this pasuk and that in pasuk 9. Still, we see that "Torah" need not be all-encompassing.

Further, it might even refer to a single section. The Torah might be synonymous with Haazinu, or the section of blessings and curses.

At the end of the day, I don't think Rabbi Yehuda must concede to Rabbi Meir's argument.