so, it's possible to trigger a redirect, (and I'll get to that) but first I want you to step back and consider your flow here.
Redirects are "slower" than just going to the right place, because instead of 1 request, 1 response, you end up with 2 requests and 2 responses.
So rather than a Redirect, I'd suggest looking at 2 things;
a) could the menu item be better constructed to go to the right place directly. Perhaps using 2 menu items with the same text, but with opposite include conditions? then the menu is ready to take the user to the right place.
b) could the destination form be better done to include both pathways - again with perhaps multiple tabs with conditions. Or a wizard form that can skip straight to tab 2 etc.
Assuming you can't make a better flow, you can do a redirect using
in the form - perhaps in the GenerateForm routine.