Google Tags, Conversions, Powr order form app

[goddessglam]

I need help with something in regard to Google Tags. I am working with a Google Ads consultant, and yesterday we were working on setting up "triggers" in an effort to track conversions from link clicks to leads. 

My site is not set up like a regular e-commerce store. If you go to any of the products, none can be added to cart. Instead, I use a third party app called Powr, which prompts potential customers to fill out and submit Powr order forms to begin an order, and then later I invoice them manually. All of my products are custom and made-to-order, and so far, this is what's been working best for me. 

So basically the "trigger" the google ads consultant is trying to set up is for when a user completes and submits an order form on my site. When an order form is submitted, there is a thank you message that appears on the same window. This is the ideal "trigger." 

However, because the thank you message appears on the same webpage, on the same url, as the product's product page, we cannot properly set this up as a "trigger." The closest we can get so far is to set the view of the product on the product page, essentially anytime the url of a product page is visited, as the trigger. 

But this is misleading when tracking conversions because using this URL won't tell me when a potential customer has committed to working with me via form submission; it will only communicate when a potential customer has visited the product page. So what the Google Ads consultant was asking, is if there is a way to somehow change the coding within the order forms so that there is a unique URL only for when the thank you message after form submission appears? So that this unique URL can be used as the "trigger" for tracking conversions.