Reverse proxy set up to workaround SOP restrictions returns 301 Moved Permanently error

I am setting up a web application that needs to hit a BugZilla JSON-RPC service to retrieve data.

In my web application, I cannot directly call the Bugzilla service from my client side javascript code due to SOP restrictions.

Therefore, to work around the restrictions, I've set up a reverse proxy on my server and am routing my calls to Bugzilla through it at:

http://localhost:9005/proxyApi/bugzilla/bugzilla/jsonrpc.cgi? method=Bug.get&params=[{%22ids%22:[39850]}]

However, I am running into a problem, where the Bugzilla RPC service is redirecting me from:

http://bugzilla/bugzilla/jsonrpc.cgi?method=Bug.get&params=[{"ids:["39850"]}]

to

https://bugzilla/bugzilla/jsonrpc.cgi?method=Bug.get&params=[{"ids:["39850"]}]

and my reverse proxy throws an 301: Moved Permanently error.

Is there any way around this? I've been at this for hours and it seems like there should be a simple solution.