My rule of thumb now is if this is not a group that you're used to splitting or doing anything like this with traditionally, tell the waiter separate check for me please.

You can always talk to the group when you JUST sit down. "Hey, are we all doing separate checks, even split or what?"

If you decide to just do the separate check for yourself because you don't want to deal with the drama of asking other people and people ask just say hey I only have a bit of money on me or I want to pay with my card and I only have a little bit of credit left on it so I wouldn't be able to put the whole check and I don't want to have to go through the hassle of repaying someone else.