I have had the same problem with non-replies. Although I just tried for a second time with one but used the GEDMatch link instead of the Ancestry one. This person is listed in both, with the same numbers. How close a relationship would a cM of 198 across 9 segments on Ancestry and 199.8 with the largest being 65.7 on GEDMatch? He has 35 people in his Ancestry tree, with no recognized names. There are three shared matches; one is my niece who is of course connected to both sides of the family, but not my first cousin once removed who is only connected through my mother. Would that make him more likely to be through my Dad? One of the others is a person to whom I have also written without a reply. Hopefully, I can receive a reply this second time.