But that attack roll isn’t a group attack. This is a group check. You are testing the skill of the group, and part of being stealthy as a group means making sure nobody else makes any noise as well. The group supports each other.

Those kids are going to be shushing, watching, keeping everything stable so it doesn’t wobble… Yeah, the 20 is doing well enough to catch the jar.

If a single success is not a success, a single failure should not be a failure.