A Church that can promulgate for the entire Roman rite an ordination ritual that is of doubtful validity, or, as in the case of the ordinations of bishops, an ordination ritual that is of doubtful validity, or, as in the case of the ordinations of bishops, definitely invalid, is most certainly not the Roman Catholic Church, for in this matter the Church is infallible through the special assistance of the Holy Ghost:
Yes and no. It's not that simple.
1. You would be absolutely correct, without question, if...the new rites were the ONLY rites. If the modernists had explicitly outlawed the old rites. But they didn't. So there's parallel rites in existence.
2. This parallel situation is unique. We know the old rites are 100% legit and from the Holy Ghost. Even the V2 modernists (every single V2 pope) has allowed the true rites to be used, in various situations.
3. The new church is advocating for BOTH rites; but obviously pushing the new rites and simply allowing the old in very limited cases (i.e. Ecclesia Dei/indult).
4. So we have a situation where you can choose 100% valid rites or doubtful ones. The choice is clear.
Your statement only works if the new rites were the ONLY ones used in all of new-rome, for the last 50 years. But the dual rite situation makes it clear that the new rites don't have the infallibility protection, nor are necessarily from Holy Mother Church, nor....and this is the most important point...are they "promulgated for the entire Roman church" because the old rites can still be used, thus the new rites are not required, nor commanded, nor an obligation. Thus, they are not "approved rites" in the historical sense of the term. Non-approved rites have no protection from the Holy Ghost.