1) Welcome to the Party!
2) As you are obviously new here, I have some suggestions to help us all help you:
When you post, please post your entire configuration including (but not limited to) your installation method (7.X.X?) and vicidial version with build (VERSION: 2.X-XXXx ... BUILD: #####-####).
This IS a requirement for posting along with reading the stickies (at the top of each forum) and the manager's manual (available on EFLO.net, both free and paid versions)
You should also post: Asterisk version, telephony hardware (model number is helpful here), cluster information if you have one, and whether any other software is installed in the box. If your installation method is "manual/from scratch" you must post your operating system with version (and the .iso version from which you installed your original operating system) plus a link to the installation instructions you used. If your installation is "Hosted" list the site name of the host.
If this is a "Cloud" or "Virtual" server, please note the technology involved along with the version of that techology (ie: VMware Server Version 2.0.2). If it is not, merely stating the Motherboard model # and CPU would be helpful.
Similar to This:
Vicibox X.X from .iso | Vicidial X.X.X-XXX Build XXXXXX-XXXX | Asterisk X.X.X | Single Server | No Digium/Sangoma Hardware | No Extra Software After Installation | Intel DG35EC | Core2Quad Q6600
3) You refer to a specific php file, without a link to its source. This is a universal internet nono. Those who follow will not benefit from your question/thread (ie: the file to which you refer). Those who may have an opinion but don't have it in upper memory have no link to click on and refresh their memory, thus you are missing opportunities for help from that missing info. In future: Always include a link to your reference source. Helps everyone. Onward.
4) Try this URL on your vicidial server:
/vicidial/help.php#campaigns-dispo_call_url
And then refer to this feature in the Vicidial manager's manual. Note that this feature related to (and shares code and many features among:) Start Call URL, Dispo Call URL, No Agent Call URL, Web Form, and even Scripts (which has a handy dropdown to insert field codes).
While these expect to be fed data from the submission, they can also be php scripts capable of reaching into the Vicidial database to get any data and even executing curl and system commands.
Happy Hunting