@the little I know
Well, the issue was is Yaakov avinu lo mes literal, and u then switched it to whether it applies to others and I would like to note that. The idea of Yaakov avinu lo mes was said about the previous rebbe. The Rebbe said “And the Previous Rebbe, who did not die, like Yaakov Avinu”. There is also a source from The bnei Yissachar which says “a tzaddik that didn’t have hanauh from this world, on the day of his death, only appears as if he dies but really lives bguf. The Rebbe Rashab says people who merit there “deaths” are interpreted loosely by hashem and they are concealed in some way. And in chabad teachings it explains that moshiach will have eternal life. There was a psak din which said that eternal life applies to the Rebbe BEFORE gimmel tammuz. The Rebbe himself said that moshiach hador has to be in a body, so if any antis believe he is nasi they have to believe his is alive. Reb Yoel Kahn, much to Seichal Yashars dismay, is on video saying nothing happened gimmel tammuz. He is here just as before.