Well, it is a little silly explanation ... true ...
But (and feel free to corect me) Minsc allways seemed from my limited resources, like a little silly character.

Yeah true. But at least he had a more reasonable and intelligent backstory. He was a little crazy because of a head injury, and so what made him so funny and enjoyable was that he was a little nuts in the head.
But him being alive with some ridiculous story about the Statue of him, it just seems a bit of a forced stretch.
But hey, I'm not just picking on him. Volo's, "I'm still alive even though I'm human" story is equally stupid.