Checking it down

[Rottersod]

At some home game tourneys we have a rule that if you openly ask or tell another player to check it down when someone is all in you receive a 10 minute penalty. The hosts announce this before the start of every game and again before the start of the FT.

In OP's situation there isn't anything they can do at that point unless they had some rules in place. Just give them a stern warning and let them know it will be a penalty from now on.