We use Google Tag Manager in addition to Google Analytics your documentation didn't quite work.

We think we figured out a work-around but haven't tested it robustly yet.

We adjusted your documentation for our internal use, and shared a version of it at this link for you. It is just a draft -- so it may or may not be of use to your devs, but I thought I would pass it along
- https://docs.google.com/document/d/1ebwl7UTfgHZOz9oqkiBH4raudz_2iFvxku8drZEyhCo/edit?usp=sharing

I also wanted to (politely) point out that it took us over 8 hours of work to develop, test, and document the GTM + GA4 solution we shared with you, so if you your team finds it useful, we wouldn't say no to your crediting our account for a month! 😉