No.
This is hard to explain, but I'll try.
If you plug, for instance, a Guitar into L/Mono Input, and a Bass into R Input, then, at the split, pan A (L/Mono Input) hard Left and B (R Input) hard Right, then, at the MIX Block, do the same, you'll get totally isolated Guitar and Bass signal paths.
You cannot, however, Pan EITHER to one output OR the other. Whatever comes down the A/B Paths is going to BOTH Outputs, in the balance set by the Output Block Pan slider.
IOW - you can get MORE/LESS of one or the other, but it's going out BOTH Outputs.
By connecting your Amp2 Input to the R Main Out, you're routing the Amp1 signal into the Amp 2 Input. You're also possibly routing the Path B signal into the Amp1 Return, depending on how the upstream Pans are set.
That's why I suggested that you use a Send R Block on Path B with the MIX Block's B Level OFF and the Right (RING) Send to Amp2.
That totally isolates Path B from Path A, preventing Amp1 from hitting Amp2 via the Right Main Out.
Make sense? No? Trust me on this. As I type this, my guitar is on L/Mono In, my bass is on R In. I have Path A set up with guitar FX, Path B with bass FX.
Path B is routed out the SEND to my bass amp, Path A is routed out the Main Outputs to my Mixer (with input from my laptop for backing tracks) and on to a stereo amp.
And never the A/B twain shall meet!