Yankel berel, you are waiting for answers you won’t get.
Regarding Yaacov Avinu being physically alive Menachem Shmei can argue non-stop. But Menachem Shmei is eerily quiet about the Lubavitche beliefs that the rebbe is running the world, that they can pray to him, that he’s everywhere, that he never made/makes mistakes (remember he’s still physically alive so he is still not making mistakes)…
Just the same, Menachem Shmei will not answer on the Ramban’s and Rambam’s psak on a moshiach sheker not fullfilling the prophecies during their lifetimes and how it applies to their moshiach sheker because he’s afraid to tell you that he believes that his rebbe is still physically alive. He knows when he will “sound like a legitimate talmud chachum” and when he will come off looking stupid…
This is a crucial part why Lubavitche NEED their rebbe to have been buried alive because if he is still physically alive his “nevuah” can still come true.