The Old Catholics rejected the dogma of papal infallibility defined at V1. I do not reject that dogma, I preach that dogma to those sedes who insist it is actually the dogma of papal impeccability. So that remark about being an old catholic is truly stupid. It's as stupid as one who concerns himself with defending or protecting the Church's indefectibility and giving himself the title of being an "Indefectibilist." Ridiculous. Christ is the Church, Christ and the Church are one and the same. That's why the Church is indefectible and the gates of hell will never prevail against her.
The pope is not the head of the Church, Christ is. The pope is His vicar, or representative on earth, the pope is God's problem, nobody else's - we know that ALL the conciliar popes have preached heresies, yet they ALL believe that all councils are infallible, V2 included. But unlike sedes, they really and truly do believe this. They believe that the Holy Ghost "moved through the council" and on that account believe all the V2 heresies are Catholic truths. This makes them material heretics, not manifest heretics. Until one of them says something like: "I don't care what the Church always taught, the Church was wrong, I say that henceforth..." they are not manifest heretics.
Nobody can depose even a manifest heretic pope because the Church is not a democratic Church, it's government is hierarchical, that's just they way it is. Only a future pope can depose a dead pope, that's just the way that is. While I am sure that all of this I've said seems heretical or perhaps blasphemous to you, we have zero need to concern ourselves with deciding the status of popes.