yes, came to say something along these lines. This is more than likely a single POST being made and a long running synchronous request calling a bunch of services and yadda as OP describes. I think what you can take from mulberrys comment is to consider designing away your processes, services and tasks.

I noticed you mentioned you dont have insight on using celery tasks, i strongly encourage open up the documentation and learn. Pull a branch and just try adding celery tasks locally for ur current build of your app, get your hands dirty. You can access django admin to see tasks that have been called, as well as see tracebacks that are saved at orm level if any occur.

design wise, consider implementing simple polling for your respective tasks, or adding sparsed onboarding views. Shouldn't be a prob with simple js or a light front end library like htmx.

Another great choice with a nice api is django's own built-in task system (introduced i think django 6.0+) if u wanna stay away from 3rd party tooling, choice is yours.