Thank you for working on this! I had a quick look, and next week I'll get you some more accurate dimensions to work with.
There is room vertically for one fan and an RPS-200-12-C, but it would require some changes to your design.
Also, since there's literally only about 40mm clearance with the fan mount installed, this adapter plate would have to sandwhich the fan mount between the adapter and the RPS-200-12-C. I see you have a recessed area for the RPS-200-12-C (which is very smart!), but it still appears to take away 2mm from that 40mm clearance, when the RPS-200-12-C specs show it being 40mm in width (is this correct?).
The 40mm clearance means you can't put the RPS-200-12-C next to the 24pin ATX connector (usually top fan position).