As far as I'm aware, and I welcome anybody to correct me if I am wrong, you need simply an average of 90 UMS in each paper at AS(*) and atleast 90 UMS in both of your A2 papers for an A*.
You scenario kind of confuses me and I'm too tired to re-read it, but hopefully that should make it clearer for you?
*By average in AS I mean a combination, so maybe 91 and 89, 95 and 85, etc.