Hi jeremy
I worked 20 years as a croupier so yeah i know where you are coming from, although harder work I would go in on the manual route, the table cloths are very thin and all the staining is from dirty hands and dirty chips.
Most of the staining is around the drop box (where the cash goes) and where the dealer stands.
maybe an idea is to spray with a solution and agitate in with a brush (lightly) terry towel, mitt and then just extract (dry passes)
With 70 tables, your looking at 30-40 mins each table.
Regards
Martin