I'm not sure exactly how dynamic the content of your secondary form is, but it seems to me that
you should probably have multiple beans with multiple pages. i.e. currently you're trying to do this:
form 1 --> action --> problem form
where what you really want to do is
form 1 --> action --> form 2a || 2b || 2c
based on the input from form 1. This is the cleanest and most easily maintainable design. The other (and much less preferred) option is
to design a form bean with all possible input fields. But this is very difficult for someone else to read and understand.