I think that everything is easier than it seems. The whole reason is always money. Most likely 4 years ago some kind of contract was signed, on the basis of which, Asa received a certain payment for his work. The developers did not make big plans for the game and didn't have high expectations. But time passed and donations grew, and disagreements about(over) work and money grew. Perhaps Asa decided, that he will not do such a large amount of work for the same money, that was agreed at the beginning. Moreover, he may not get percentage of sales. The owners refused to pay Asa more, referring to the contract. Therefore, there was sabotage in the work and disruptions in terms, as well as Asa's desire to leave the project.
Remember, that everything is always about MONEY.