". . . Now, seller is saying that they had the approval by the time I cancelled and they told me right after my notice. . ."
Gosh, that still sounds like it was
after 60 days had elapsed, doesn't it? Are they using the same calender . . . . you gave them 30 days beyond what was required!
Did the revised and corrected "approval" arrive as promised within the 2 days?
Continue to document the sequence of events and their dates, as you have.
Do you have an Attorney involved in this? A Buyer's Agent?
Do you still want the house?
Did anyone have guts enough to put in writing the basis upon which they would withhold your EMD? Who's holding the EMD in Escrow (I hope)? And who's threatening to retain it?
Hopefully, it's not in the possession of Short Sale Seller!