Along the lines of the old adage where "opinions are like ..., where everyone has one", I'm sure there are posters here right now who consider sedevacantists schismatics. We occasionally get posters who consider all Traditional Catholics schismatics and who sneak on here in "disguise" to troll and disrupt the forum. So anything could have been posted along those lines at any time.
Now, there's another angle on the CMRI from the SSPV et al. where they claim that they're schismatic because their original founder, +Schuckhardt, received ordination and consecration from an Old ROMAN Catholic, Daniel Brown. That is such a mendacious position that I largely lost any respect I had for this group since Canon Law clearly states that the penalty for receiving orders from a schismatic is SUSPENSION. In other words, you don't become a schismatic for getting Orders from a schismatic ... it's a grave sin and you incur suspension. Nevertheless, given the state of crisis in the Church, I don't think those provisions would even apply. Recall that this happened before the SSPX had been heard of and before the +Thuc line bishops were anything ... this was 1971, and they were in fact the very first Catholics to start questioning the legitimacy of Montini. But worst case, Schukhardt would be suspended and this absolutely does NOT make the CMRI Old Catholic schismatics. CMRI had one elderly priest who was providing some Sacraments to them, and they were legitimately concerned that they'd lose access to the Sacraments once he passed away, since, as mentioned, there was no SSPX yet, no +Thuc line bishops, nothing ... just pockets of individual priests here and there. Of course, Brown was an Old ROMAN Catholic ... but most Trads, including clergy, don't know the difference. So, the Old ROMAN Catholics split off from the Utrecht group precisely when and because the latter rejected Vatican I and papal infallibility. So they did NOT follow them into the heretical positions of the Old Catholics. Their canonical irregularity stemmed from the fact that the See of Utrecht appealed to some agreement they had with Rome to confer Orders without papal approval, whereas Rome denied it. So, in this day and age, the remaining Old ROMAN Catholics out there, including one Bishop Meikle ... they're in no different a situation of canonical irregularity than any Traditional Catholic might be.
But, anyway ... in the WORST CASE, the CMRI were not Old Catholic schismatics as the SSPV have continued to allege. Now, when +Schuckhardt went nuts after having gotten addicted to prescription pain killers (originally for a legitimate reason) and started at least privately referring to himself as Pope, and engaged in some vices against purity and contrary to nature, the other CMRI priests rebelled and kicked him out. So not sure how Schuckhardt's later insanity made the entire group schismatic either.
I'm no fan of CMRI, BTW, and have serious disagreements with them on many issues. I just believe in fairness and truth.