1996 Toyota RAV4 Oil & transmission leak

The following were done due to an oil leak in Feb by the local Toyota dealership. Removed & replaced valve cover gasket, distributor O-ring, oil pump seal, oil pump o-ring, crank shaft & seal & cam shaft & seal. In addition the timing belt was replaced. I asked how would we verify that the oil leak problem was resolved, & they said, when you get your next oil change. I took my car to today to get my oil change (same oil replace place that found the original leak) & my car still has an oil leak & the dipstick was "off stick". I'm planning on bringing the car back to the dealership. Since all those items were replaced in February, what could still be causing the leak, what repairs would fixing it entail? Finally. What might the approximate cost or # of hours be to resolve the problem.

Thanks in advance