Getting 50X from worker route path

This route mydomain.com/WebProxy.asmx/someactions is configured as a worker route and response with 500-Internal-Server-Error.
some findings:

  • Removing CF DNS proxy is solving the issue - proving this is not a my system issue. this also works with DNS spoofing using /etc/hosts to directly access the GCP LB or the application server.
  • Response using curl show that the response comes from CF:
< cf-ray: 76b97f97bab594e0-HFA
cf-ray: 76b97f97bab594e0-HFA
< alt-svc: h3=":443"; ma=86400, h3-29=":443"; ma=86400
alt-svc: h3=":443"; ma=86400, h3-29=":443"; ma=86400```
stuff I tried:
- Removing that entry entirely from the worker routes
- Restoring the entry only this time with `*`  - `mydomain.com/WebProxy.asmx/someactions*`  causing another different response from CF - this time a 503.
- Purging that path
- Removing mydomain.com DNS entirely and restoring it again (attempt to refresh CF)
All failed.