There is a big difference between "formal positive COVID test" and "just guessing". For the case I mentioned above, tests were effectively unavailable at time of illness. But later on, multiple doctors said that from the symptoms and the follow-on illness, it was probably COVID.

Your insistence on denying distinctions like this makes you look like a person arguing a case, not somebody trying to jointly get at the truth. Which from my perspective, makes you much worse at arguing your case.