An EVENT SEATING only counts as fulfilled if all customers in the group could be seated within the tick. Otherwise the attempt counts as failed and the EVENT group will leave the restaurant.
Does seating still happen? So is the SEATING tick load increased for the waiters that seat a part of a group only, even if the group leaves?
First, note that the specification (page 16, lines 19–26) separates two things:
Work performed by each waiter: If a waiter seats part of an EVENT group, those customers increase that waiter’s SEATING tick load.
Success of the whole attempt: The EVENT group is successfully seated only if every group member is seated during the same tick.
Yes. The partial SEATING actions still happen and increase each waiter’s SEATING tick load, which is not decreased if the overall EVENT seating attempt fails, and the entire group leaves.
Btw, EVENT customers do not increase the waiters’ current load (page 15, lines 24–28).