Balk Question

[LDUB]

I just thought of this one today.

Runners on first and second. Pitcher balks. Runner who was on second goes to third but runner on first does not want to go to second. Probally because they have a special first and third steal play or something like that they want to do. So my question is does he have to advance to second or can he stay at first. I know that awarded bases means the right to advance without being put out, so I would think he would be able to stay at first, but I don't know for sure.