We have the word of one man. No one else backs up his claims. There are many MANY people within the verse that could and should gather this evidence.
No one should ever take just the word of a man.
We have no evidence to back him up.
Thats my point, we blindly follow his words, then whats the point. He could tell us She was the Off-Spring of Big Bird and Kermit the Frog, you would believe him because he said, no you would want more evidence....though granted her Hair does resemble something 'Muppet' like.......
All the other major facts in the show are verified from numerous sources....except this one.