From what I have seen in regionals, he throws a lot of stuff with pretty strong, pretty standard layouts. Nothing fancy.
He doesn't get a lot on the ball, and he naturally chooses a layout that will give him a more flare potential in many cases. Other times, I'm sure he uses pretty weak layouts, as he likes to be able to go as straight as possible. However, I also know that he uses speed and hand position changes first...
Last year at one regional I saw him throwing a ball with the pin over the fingers and the cg kicked out some, and another ball with the pin next to the fingers with the cg right below. Both balls were sheen finished.
I don't know his PAP, so I can't say for sure what the drillings actually were, but I think you can get my point that he doesn't really mix it up. There's no RICO or anything.
Just go with a pretty strong, versatile layout for your friend on a ball that has a lower RG, medium differential, and moderately strong cover. This should allow him to play pretty far right or left (depending on his dominant hand, obviously), and give him a nice midlane read with a strong arcing backend reaction on your THS.
Hope this helps, and sorry nobody pays much attention to what the Traber bros. are throwing.