Is anonymity possible using Qubes OS without DarkNet?

Hi wise people.

I got a situation here: 1. I need to test a web app for a client. 2. The test must be anonymous, or Blue Team won’t take it seriously. 3. I cannot use the DarkNet because the app does not allow connections from DarkNet servers.

So, up until now, my best bad idea is to get a dropPhone, and go connecting at some random place using such phone’s hotspot wifi.

What do you think of this? Am I way too stupid? Is there any technical fixes that may turn this into a mediocre idea? Is there a better, known way to do this?

So sorry if this sounds a bit offtopic, but I honestly think that it is not, that this is a situation that other people may get into.

Thanks in advance for any tips, hints, or discussion.