Yow!!-- sorry for the late reply, and I agree with kt17: that is one amazing bit of research, and it manages to check off all the boxes-- incredible!! Many thanks for that.
FWIW: I couldn't find any similar incidents, and I couldn't find a specific reference to a beer spill at a ballpark being an "April shower." Also, other networks had that same film clip besides ESPN, so... not sure. That would be pretty amazing to have a clue based on a single incident, but some of the clues in this particular puzzle seem so obscure (and unfair), I guess it wouldn't surprise me.
Anyway: many, many thanks for all your efforts, sincerely appreciated, it was a truly amazing find! 👍