There are no stupid questions. Handball by the keeper outside the box is not an automatic red card. The keeper has to be stopping a goalscoring situation for it to be red.
I did a game at Barrow and the away team cleared their lines. The Barrow keeper was about 5 yards outside his box and, basically, lost his bearings and just caught the ball. Yellow card and free kick as there wasn't another single player in that half of the pitch. Also ball not travelling goalwards.
Assessor told me I should have given a red. When I got his report I appealed to the FA and they agreed with me and the assessor was sent for re training.