Script dependant on radio button selected

Script dependant on radio button selected

I cannot define my radio button...

How it is setup now:

When the user selects the "Recall" radio button as the "Appointment Type" the hidden field "Recall W.O.#" shows.... this works great, however, I need the Recall W.O.# to be filled out by the user. I found out the hard way that you cannot make a hidden field mandatory, because it will not submit if not filled out. But I cannot get any script to work either.

Also, the hidden field will show if that "Recall" button is selected, OR if "Re-opened Recall" Checkbox is selected under "W.O. Status"

So, if...

Appointment Type = Recall (radio button)
OR
W.O. Status = Re-opened/Recall (checkbox)
then...
Verify on Submit that the UN-hidden Field "Recall W.O.# IS Filled Out

How???

Thanks!!!
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