Cornholer is an American rural slang expression, which the first reference appears in 1951, to name homosexual men. It could be interpreted as a hole maker or who puts the cob in the hole. It could have the meaning of making holes with corn (penis) or having sex in the cornfield.
Interestingly exists in America a bait to hunt deer that has the same name and its slogan is “Funny name, serious results! Below you have the photo of the item, which sells for $ 9.99. Please do not confuse this with a dildo!
There is also a game that involves throwing small bags filled with corn to introduce them in a hole. Apparently, the slang came from the game, meaning that to make a “cornhole” was fuck a guy, deriving to “cornholer”, who makes it.