Good luck with it! When im back on my desktop I’ll post a combined simplified script that can all go in just the HTML embed in the form, including hidden field values AND google apps script call that writes your form data to a new row on a google spreadsheet (one thats secure and isnt published to the web or using google forms).
When making the sample page i realized that something more modular (“not” having that exact particular code on every published page) would be even more useful