RealGM

in yahoo fantasy draft?

Some people in our league suspect that he set it up that way, but we can't figure out how to check.

Check all the stuff under recent transactions. You can't really start a league as custom draft order because if a player joins or leaves it's changed to random. So if there's an entry that says "draft order changed to custom" (and it's the most recent draft order entry) that means he used custom order.