I noticed something else on the list of 26 corrections that Ken Liss reported Topps was making in the beginning of 1991 that supports that the Valdez wrong birth date might possibly exist.
On the list of corrections is the #780 Randy Myers card but it's not for the 15/19 loss correction it's actually a correction of 2 losses in 1990 to 6 losses in 1990 this actually makes sense and would explain where the 15 losses came from and possibly when they first corrected the 2 losses they didn't correct the 15 losses.
So if the Valdez wrong birthdate does exist there's probably a Myers with 2 losses that exists and is as scarce as the Valdez.
91 Topps correctionsSyracuse_Herald_Journal_1991_01_28_37.jpg