rebdoniel,
I believe you may be missing a nuance in Rav Pinchus zt”l. His statement is in the person doing the act. And geris while an incredible undertaking is not an act of teshuva, rather a new bria. You have done a tremendous thing by following the pintl yid that you had some sheichus to. And although your father, i am sure did a tremendous job raising you and putting you in a position where you were able to make incredible and difficult choices for the good, he committed an aveirah as we all do. But we cannot do teshuva for our parents, each person is responsible for themselves.