Dom (along with Clint) will be close to the explosion, but miraculously unharmed. There will be a circle around the two of them (10 feet, I think we decided? Correct me if I'm wrong), and anyone in that circle will also be unharmed. Once the dust settles, she'll be yelling profanities and helping out as needed until reinforcements show and kick her out.
Anna will be with Piotr and Ali (and anyone else who wants to be there), in one of the galleries (Freer?). They'll try to support the building and evacuate civilians as much as possible as it goes down. She'll probably stay by Ali once Ali gets hit to make sure she's going to be okay, then will be sticking around after SHIELD gets there to help.
Paige will be with Lizzie, and they'll be... I forget where we decided they were, but it'll be far enough away that she's not going to be injured badly. She'll be hit by something, though, and will have a broken arm and possibly a mild concussion, but nothing super serious.
Kitty hates me. She'll be with Sam when he gets taken down, but will phase through whatever it is that smashes him. She won't be able to reach his hand in time to phase him as well. After pulling his body out, she'll be unphased for a few seconds, taking a breath to go back in and process her smooshed BFF, at which point something else is going to come down on her, hard. She'll end up with a fractured jaw, concussion, dislocated shoulder, and a few busted ribs. Also, she really hates me. A lot.