Google Maps Geocoding problem with custom Php form

I have taken over the duties of maintaining a client's website after it had fallen into disrepair for several years. The original developer had to be removed from the project and is not able to be contacted to ask him about his customizations. First of all, this project is for an Atheist church. They promote love, understanding, and acceptance of all and their members are large supporters of charitable causes. If you do not feel comfortable working on a site of this nature, please do not bid. Project Breakdown: On the WordPress site, visitors are able to apply to become ordained in the church so they can perform legal weddings. When a guest submits a form, the data is sent to a database outside of Wordpress where it is held until an administrator can review it. The administrator can choose to approve it or deny it. Upon approval the information is supposed to be sent to a php form with a google map embedded into it. The point of this is map to allow our administrators to help match clergy with couples who request to be married by the church. The issue currently is that the latitude and longitude don't seem to be getting collected correctly and, therefore, none of these members are being placed on the map. Currently, I have errors being displayed on the page and there are MANY approved clergy members whos coordinates are displaying as null,null. I am hoping there is a way to have this fix applied retroactively and not just for new approvals, but I don't know how it works. I have fixed many issues surrounding this map page already by updating outdated links, etc, and I'm sure this is probably a very simple fix for someone with geocoding experience. Unfortunately, that is not me and I am stumped.