Being able to choose from the same list of related Contacts in the same child form

I have a Sales table where at the top of the form the sales person selects a Company, then a related Location, then a related sourcing contact from that location. At the bottom of the form is where the trucking information for that sale is located and there is a spot where the person setting up the truck has a dropdown of the same related contacts from the company above only in this case the are selecting the Shipping/Receiving contact for that Company. I have this bottom contact set up as a 2nd relationship to the contacts table but using the upper company and location selection for my conditional dropdown setting, and I thought it was working fine, but now it doesn't seem to be working. Is there a better way to set this up?

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Chris Swirtz
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