As I understand the word "dogmatic sedes " I am not, nor is C.M.R.I. I know this because they offer sacraments to those who believe the chair is not empty.
We hold to the sedevacantist position but we do not teach that if YOU do not hold to the sedevacantist position you are damned. That is the Most Holy Family Monastery way. They will not accept a priest, Bishop and Heavens they will never accept a True Pope. Their fear is a True pope will definitely show them the errors of their thinking.