Yankel,
Reb yoel retracted on certain aspects, he nontheless continued to believe the rebbe would be moshiach as is published after gimmel tammuz and is attested to by any student who ever learned under him long enough to hear it. Again whether chabadniks were consistent or jumped to conclusions or added too much to what the rebbe said is for lubavitch to figure out. That has no bearing on the question of whether it can happen or not.
idk what ur talking about with the sdei chemed. He is saying if the jews merit moshiach will come from the dead., if they dont then he will come from the living. Even gil student acknowledges thats what it says. Ive been having these conversations a long time and ur “obvious pshat” has never reached my ears once. Why would a dead person named daniel be a metaphor for merit? And if its just a metaphor for merit why does the gemara mention it if it already mentions merit a daf earlier? The whole point is he is connecting the two. If we merit he is from the dead that was the safek “If from the dead”. and if we dont merit then he is from the living the safek of “if from the living”. All of this is obvious and straightforward. Even R Chaim Dov keller who disagrees with messianists didnt say what ur saying. Ur mixing up two things regarding the abarbanel. Some mefarshim say moshiach coming from the dead is a question of when techiyas hameisim is. The abarbanel does not. read any of his pirushim on nach and he always says one thing about when techiyas hameisim is. Likewise you didnt notice that he says “for we already learned in sanhedrin”. He said this because he already commented on this in the previous chelek of maayaneh hayeshua where he says all of chazal thought this was possible and over there he does not explain it as a doubt of timing as some achronim do and importantly he says this was the das of chazal and in accordance with rambams shita of techiyas hameisim bgufim.