You will need static routes in all routers (both ways). So router 1 will need a static to the outgoing subnet of router 2, and vise versa (unless you have some dynamic routing working and turned on).
Make sure you are adding your redirect rule above your masq rule in the first router or it won't work. Redirect would then need to have the actual IP of the connected device you wish to RDP to. So no DHCP, or at least it would need to have a static DHCP IP assigned to the computer. Connection tracking would need to be on as well for the first router. But I think that needs to be on in the first place for NAT to work.--