I totally agree with MickeyCheeky on this. I can't say what he has or doesn't have, but I think that if he has bipolar 2 or any bipolar type, there's also something else going on. I've never heard of a situation like his in a person with bipolar disorder only, not even in anyone with bipolar type 1. At least not a delusion or lie of his type.

My grandmother surely had bipolar type 1. Or at least she had a couple severe depressions and clear psychosis that included paranoia, hallucinations, and a couple delusions. It was the case that she would sometimes still believe she had ESP even after what might have been manic episodes. However, she didn't go around advertising it. That delusion would only show itself when a topic triggered the admission. She also never stopped believing a couple hallucinations she had, as impossible as they were. But again, she didn't talk about them, unless triggered.

I have bipolar type 1. I'm not prone to lying, but when I'm hypomanic or manic I can be grandiose and exaggerate a lot. Maybe tell a few white lies. But when I'm well, that eases/ends.

I think many people in this world are prone to exaggerating even when mentally well. Lying itself is pretty common in the population, so is the odd habit of believing such lies. Perhaps self esteem (or lack thereof) can play a part in this.

The whole "I have cancer" and "I worked at [a place I never worked]" could just as easily fall into the Somatic Symptoms and Other Related disorders realm. Or something else. Maybe a personality issue? Trauma/neglect.