I figured it Flash got in, Savitar would get in.
Yeah, but Barry had Snart. Savitar would need evil Legends mirrorverse Snart or something..
(Really though, they should be exploiting the "shared memory" way more then they have been.
Like, hide Iris and don't tell Barry where she is, but give them all these false leads that he THINKS are the real ones (He can't know he's being lied to, so Savitar doesn't know).
Then Savitar can go nuts breaking into an Argus or meta prison, only for the door to slam on the other side and he ending up trapped..
Meanehile, Iris was shrunken down with Atom tech and safely in Cisco's eyeglasses..)