There's a help/contact link on the shop log for each shop. I think it's for the scheduler. Start with that? They pay by check and the date showing on the shop log is when the check was cut. It can take 7-10 business days to reach your mailbox though.
Yes, I suspect that the 'paid' date is they date they approved payment or something because the checks rarely hit my mailbox in under 2 weeks after they are marked 'paid'. It could drive you nuts.