If you want a rotating table to stop precisely, it is called
indexing. Tell them to buy an indexing table, like by Camco or
whatever. They are designed to stop exactly where they are supposed to
stop and are adjustable with cams or whatnot. Some of them are
pneumatically operated. I sold a bunch of them in the past.

Compared to the cost of screwing around with electrics, hydraulics,
etc it is easier to spend a few grand on a proper solution.

i