If I made a casual $5 bet with a friend about a historical fact the other week, but I paid him and he immediately gave me the money back, am I still a kosher witness? Additionally, if I have had a seminal emission recently, would that be something else to disqualify me for eidus?
If you just made a casual bet, and this is not you sourse of livlihood you are still a kosher witness. The gambler that is not a kosher witness is someone who uses betting as his source of income, but not for something small like this, especially that the money was returned.
A person that had an accidental seminal emmision is not disqualified from being a witness.