The other common complaint I notice from almost every other adherent thinking their group is correct (and they are legion) is that the Catholic faith differs in many ways from their own and is wrong; well since they were only found five hundred or less years ago in order to rebel against the Orthodox, well yes it differs considerably as one would expect of any new religion, denomination, sect, or cult. They have no legitimate historical claim; only the other Orthodox can make that claim, so they are following something someone formed five hundred years ago or less, frequently far less. Of course they don’t agree with each other either and accountability is ephemeral. Can I mention Bill Gothard ?
So you're equating time in existence with correctness? By that definition Islam, Hinduism and others can make the claim their viewpoint is right.
I could make a case that the RCC has been on the "wrong" road now for over 1800 or so years. It is very possible to be in error that wrong and not realize it.
If the RCC can't point to verses in the Bible to substantiate their claims, without taking them out of context or reading something into them, then it's the RCC that has to explain/defend it's positions on issues of theology.
When the RCC is called out on their false teachings I note they often change the topic in an attempt to not address the charges.
When one sticks to the Bible, and the teachings in the Bible, you don't have to worry about that.