That's not viable. No perjury was even alleged, by anyone, so far as I know. Certainly nobody was charged with or convicted of perjury. Greer could have brought the charge himself but for one problem -- he didn't have any evidentiary reason to doubt the depositions. You can call them perjurers all you wish, but that's defamation unless you can prove it. I don't think you can.
Well, when someone says "A, definitely A" in their testimony, and then says "well, actually it was B" on cross-examination, with A and B being completely contradictory, that fits a reasonable man's definition of perjury.