[engine limitation, wait] Hive Mind & Pact of Negation

[HarlequinCasts]

Describe the Bug:
#1 Can't seem to get Hive Mind to force opponents to cast a copy of Pact of Negation.

#2 In the attached save file, if I cast Brainstorm, Hive Mind causes the AI to cast a Brainstorm copy. If I then Pact of Negation the AI's Brainstorm copy, the Brainstorm card remains on the battlefield (see attached screen shot).

Possibly relevant: my original Hive Mind / Pact of the Titan post here.

But I assume this is some interrupt vs instant shenanigans with triggers?

Which card did behave improperly ?
Hive Mind & Pact of Negation

Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
PtTv1

What exactly should be the correct behavior/interaction ?
AI copies Pact of Negation and hopefully loses the game on the following turn ^_^

Are any other cards possibly affected by this bug ?
NA

[Korath]

I definitely call shenanigans.

Might, maybe possibly, get fixed as a side effect of "when you cast" triggers triggering at the start of the interrupt window instead of just after its end, if that's even A) feasible, which I doubt because of all the random stuff coded to trigger on spells being cast that aren't actually worded to, and B) ends up working right. Otherwise hopeless; Hive Mind can't trigger until it's no longer legal to cast interrupts.