[aeon48m]

That's exactly what happens

Actually, during my playthough, I hacked the Mjolnir and then burned away outside of hacking range and then it was never re-hacked, and I was still able to use it to destroy the target.

[Ryuseiken]

That's damn impressive considering it only gives you 30 seconds IIRC.

30 seconds to hack it.

Followed by a 30 second window to fire it, just tested it and, in my case, after 30 seconds they regain control and the elder jumps out.