woah didn't think of that
But he's basically done that already, when he tricked Seth into giving Anubis that curse on his arm. That's why Seth says in chapter 38: "If I get rid of Osiris, Anubis will probably vanish along with him (since Osiris' flower, that is keeping Anubis alive, will wither if Osiris disappears). But, if I give up everything (including, the wish to destroy Osiris) and go to Duat , Anubis will continue to live." That's when Seth found out thanks to Isis that Anubis' life was in Osiris' hands even *before* he gave him the curse on his arm, as Anubis had only been living on borrowed time ever since his suicide attempt (from when Anubis killed himself after fighting with Seth, ending up in Duat and meeting Osiris there) and the only thing keeping him alive ever since then (and which Osiris had been using in order to be able to repeatedly possess' Anubis body) had been the flower that Osiris gave to Anubis, back then.
What if Osiris blackmail Seth with him trying to kill Anubis if Seth doesn’t go to Duat?
Or what if, Anubis hurting himself or trying to kill himself and tell Seth the only way that can save him is if Seth go to duat. imsoexcited for s2