The CMRI priest would be a good one to contact concerning baptismal validity. The SSPX will dismiss out of hand any doubt in the case of NO baptisms, barring hard evidence. While I have little experience with Eastern Rites, their theological and philosophical perspective is pretty different from the West, and they likely do not focus so much on validity/invalidity, matter/form/intention, etc. I recommend a sedevacantist Roman Rite priest, as they will look at the NO baptism critically and with the same set of guiding principals with which you are likely familiar.