pretty sure i call this river either, if anything i might consider raising the river since he could think you're bluffing if he has Tx or he could even have some weird Kx in his hand.
remember the guy plays almost 50% of hands so his range is crazy wide.
one thing you didn't mention despite the super small sample is fish' AF, if its like 0.5 i MIGHT consider a fold but if its like 3+ i probably jam