"Okay, so you maybe have friends, there goes my afternoon, huh?" [Queenie, you want I should set this guy up somewhere other than the existing terraformed asteroid?]

[Please don't put him on the Joker's asteroid, we'd be sad.]

"Of course not," says but-a-man.

"All right, don't say I didn't warn you," says Bella. She teleports him temporarily to an empty residential section of Saturn and then teleports to a good-sized Jovian moon (no point putting her prisoners right on top of her citizenry) and installs basic terraforming before going to fetch him. She decides to wait for a reaction before installing anything beyond atmosphere and livable temperature to the place.

"Comfortable," he rumbles.

"Mm-hm. Any preferences on the accommodations beyond 'not instantly fatal'? I'm not interested in doing you harm, I just can't have people nuking stuff."

He shakes his head.

"Well, welcome to your not instantly fatal new home, I'm going to go round up some more revolutionaries, you'll have company," Bella shrugs. And she stealths and teleports to whoever may meet the description of this guy's second-in-command.

There fails to be such a person.

Who was the first other person to find out about the plan with the nuke-explainer, then?

A very pretty woman walking along a mostly empty street.

The woman walks faster without answering. This is an entirely reasonable reaction if someone is following you closely on a Gotham street.

"You know the guy who just brought a nuke to the stadium," Bella states.

No reaction.

"So yeah, I'm not a random person who decided to follow you down the street," Bella says, folding her arms, "I'm a powerful busybody and I have some questions."

The woman draws herself up and looks at Bella in cold silence.

"I am completely prepared to leave you on Ganymede forever. Would you like to produce any reason for me not to do that?"

She says nothing.

A highly suspicious underground chamber that both looks and smells like it is part of a sewer system!