So basically I’m trying to break the wombo combo of Verena by using Imperial Dedication class card from Inspiring Leadership, what’s the result of this interaction?

Verena uses Combat Mastery, resolves first attack against figure A, then chooses figure B for the second attack. Wannabe Smart Imperial player (me) exhausts Imperial dedication (figure B is adjacent to figure A) and says target must be figure A. Does Verena still resolve the attack, bypassing the “Each attack MUST have a different target”?

Yes it’s a very rare and tricky situation to be in, I’d be very glad if someone clarified!

Imperial Dedication has "who could also be the target of that attack". Due to the restriction of "different target" Verena cannot choose A to a target for the second attack, because A was already attacked before and thus cannot be a target of the second attack ("that attack"), thus cannot be chosen by the imperial player when resolving Imperial Dedication.

I.e. there's a distinction between "a valid target for an attack" and "a valid target for that attack".

(Also note there is a threat cost in addition to an exhaust cost.)

Oh thank you a1bert for your clarification, I can see now!

(Yes of course threat cost for the exhaust)

@a1bert what happened in the end was the exact opposite, Verena declared an attack against figure A, I used imperial dedication to make her attack figure B. Following what I could understand from your clarification we didn’t let her use her second attack against figure A.

Well, if you switch the target from A to B, B becomes the target of that attack, and A is not the target of that attack. She didn't attack A, and could still choose A as her second target.

****... there’s no way then^^ I thought I got it but failed again