Foley would because he'd know he could do good promos on him and that Flair would be forced into a WWF style match, where Foley thrived doing what Flair said would have him in a wheelchair. His desire to put out good work and prove Flair wrong would beat out any animosity because that's how Foley works.
Austin could go either way. I think he'd see Flair's worth in the feud with Vince and we get a month or two before Flair goes down the card, at least. Flair would also have no issue putting anyone over at this point, especially if he wants to build enough goodwill to make money. If any spot is taken.
Rock and HHH would be in, though. The only spot he'd take is Taker's, and he's hurt so it doesn't matter.
I don't think he undercuts Jericho, however I do think he is the deathblow for Big Show for a while. He definitely doesn't undercut the Radicalz and if anything I think he helps the Radicalz because he would probably get paired with them.
Flair/Angle also happens and you know Flair wants to take credit for that, too.
