Well this was told to me by an F-16 pilot based at Masroor. He used to come to my flat in i Clifton .Entirely not true. The seats were functioning just fine. 5/6 pilots who ejected in the 90s were recovered safely.
I Don't know if he was being boastful, or some F-16,had this issue and others were fine.
Yes there were successful ejections in the 90s from PAF F-16s, last in the 90s being in October 1994.