The whole curriculum of this "school readiness" program is intended to be behavior modification. The "currency" issue is thorny, because communicating on the basis of meaningful "currency" with my DD raises the stakes and generates a anxiety related spiral that often results in total non-compliance.
BTDT, totally, my sympathies. We have sometimes had success with "low value currency"-- that is, something that's just barely worth working for, but doesn't feel life or death. ex. not working for video games, which DS feels strongly about, but working for the option to choose what's for dinner, which he doesn't think is a crisis if he doesn't manage it. This is hard to calibrate.
If the school is supposed to be doing behavior mod, it sounds like your DD is kind of out of their league? From your descriptions it sounds like they have given up and are letting her escape when she wants/needs to. I wonder if you could get another opinion (from a BCBA) about first steps to change that situation.
DeeDee
