Further cleanup on previously shared participant form

Further cleanup on previously shared participant form

This addresses some variables that were being set in one place
& used in another. In the past this was done because the
form prepared variables for use in a shared function.

However, the previously shared code is only used by
this form now & hence can access the submitted values in
a more consisent way (not having to  deal with
the values being possibly presented in a range of ways