My impression (mostly from coverage that I've seen at UnderstandingWar.org ) is that Yevgeny Prigozhin might be happy to admit to quite a few things - whether or not he'd actually done them - so long as doing so advanced his public image (hint - neither "weak" nor "pro-American") and political ambitions. Pass the salt?
The guy spent years publicly denying the existence of the Wagner group, then opened a patriotic co-working space literally called The Wagner Group Centre. (meanwhile, the group itself is still illegal under Russian law)
I'm not saying he didn't interfere in the elections, but whatever he says is no proof either way.