Just an update a GM ticket was replied to and while the GM didn't directly state #1 is griefing, they did state griefing is against the ToS and they'd investigate griefers.
Still, there's been no answer to #2.
There's been no reply to #4 either.
There really should be a harder line drawn on what's griefing and exploiting as well as what happens to those who exploit. Until this is done people will just do so for the lolz since there's seemingly zero enforcement on these issues.
In the mean time, if nothing else you can create 2 tickets if people are knowingly exploiting in matches. 1 for exploiting and 1 for griefing as a result of the exploit. Maybe someone gets dinged for tickets created.
Perhaps create a community ticket for the poor communication on these issues and a second community ticket for the poor QA/code merger process that keeps allowing the same bugs/exploits to reappear in the game.