Is it possible to set up a conversion so that the ad ID gets into the Request?

Question

Google Ads

Good day to all!
There is a working context of the company, advertising leads to the landing (Site A). We track conversions (on a click to order a call back, on sending a contact form and on a click on a button - fill out a questionnaire leading to another domain (site B)).
As a result, we get questionnaires (which are filled in on domain B)
People filling out questionnaires from a variety of sources - instant messengers, social networks, advertising fb, vk, google. And to keep track of how many questionnaires were actually filled out is unrealistic.
Hence the question - is it possible to track this somehow, for example, when switching from advertising in the line, we have the identifier "...?utm_source=google&utm_medium=cpc5&gclid=EAIaIQob..." can it be obtained somehow by a script? So that later this identifier can be sent along with the application in the form or further to domain B, so that it can be saved there with personal data.

Answer 1

add hidden inputs to the form and fill them with script
1. Inputs:
2. Helper function to get UTM tags from URL

function getURLParameter(name, url) {
    if (undefined===url) url = '';
    name = name.replace(/[\[]/, '\\\[').replace(/[\]]/, '\\\]');
  	var results = new RegExp('[?&]'+name+'=?([^&#]*)').exec(url || window.location.href);
  	return (null===results) ? null : results[1] || true;
}

3. Filling in inputs on the example of utm_source

if (el=document.getElementById('utm_source')) el.value = getURLParameter('utm_source');

Answer 2

Set up cross-domain tracking and you won't need to invent anything. All data will appear in GA reports
https://support.google.com/analytics/answer/103434...