No, Jackson was standard Jackson until....he died. He came back and was hinted to be absurdly powerful yet still got nearly knocked unconscious by an alternate Midnighter.
You forget that this is Union after Jackson revives him. He wasn't very powerful at all. Monarchy Union wasn't even Songbird level, much less Green Lantern.
Most of the members were practically street levelers. Here is the break down of what will happen to each member in this fight.
Vox: Killed by a stray blast.
Caleb: Killed by a stray blast.
Metropolitan: Killed by a stray blast.
Christine: Killed by a stray blast.
Union: Killed by two stray blasts.
Malcom: Was active for basically one issue and did nothing.
This leaves Jon, Professor Q, and Jackson as the only people worth mentioning. If we give Jon the benefit of the doubt, he can take on one person from the opposition. Professor Q hurts the team as much as she helps; Henshaw can hijack her tech. Jackson might put up a fight but goes down.
It's hard to use The Monarchy in forum matches. It lasted 12 issues and most of those issues were spent constructing the team. If it hadn't been cancelled, maybe there'd be more to work with. Jackson might have solo'd if he had more feats after his rebirth.