If you are opposed to Sola Scriptura, supposing that tradition is necessary to provide authoritative tradition, you need to make sure you have the right authoritative tradition.
While you have no doubt heard the usual anti-Sola-Scriptura argument that there are ba-zillion (it's a technical term) Protestant denominations, possibly you are unaware that there are good deal more than one "tradition" group.
The largest "tradition" group (by headcount of supposed members) is the Roman Catholic Church (typically claiming to be about 1 billion strong). There are, however, some within the Roman Catholic Church who claim that it has been hijacked (see the discussion here) - and it would not be the first time such a claim has been made: at one time there were three different men claiming to be the "real pope" and of course denouncing the other two as anti-popes.
On top of that there is Eastern Orthodoxy (which claims to have about 300 million members).
And then there are the Coptics, Nestorians, Armenian Catholics (not to be confused with Roman Catholics), most of which generally hold to different traditions than the EO and RCC folks, but sometimes getting subsumed in the head count of one group or the other. Also, there seem to be at least some Anglicans who hold to "tradition."
So - which "tradition" is the correct one?
One usually hears the claim that a "referee" is necessary to decide competing interpretations of Scripture. If that's so, isn't it also necessary there be a "referee" to decide competing claims of "tradition"?
Of course, a consistent Roman Catholic or Eastern Orthodox or Sedavacantist Roman Catholic will deny that a referee is needed: and we cannot fault them there. Instead, we fault them for claiming that our epistemology is flawed on the basis of a lack of referee, when it turns out the same criticism applies to their own position.