Ringback tone by incoming route - possible?

Hi all,
I’m running in international call center on FPBX 2.11, and I’ve run into a weird issue recently.
Since the majority of our customers are coming from Europe, I’ve set our country tones to German.
We have now recently expanded to USA and Australia, and I have received several mails from customers like
"I tried to call your support line, but I just hear something beeping." - which I figured was them mistaking the
German/European single-frequency ringback tone for some kind of error beep, since they are used to their own more “melodic” ringback tones.
Is there a way to assign different ringback tones to different queues/routes/inbound-DIDs? That way, I could just assign the AU ringback tone to our AU freecall route etc…
Some guides I found on the internet tell me to set the language for that route to en_AU, but FreePBX deletes all country definitions from indications.conf except the one currently set as default for Asterisk… and indications.conf seems to be one of the few config files that does not come with a _custom.conf add-on file.
Is there an alternative approach to that, or a feasible workaround for the lack of _custom config options?

Thanks to @dicko and @jerrm, see a solution here

I just opened ticket FREEPBX-17209](https://issues.freepbx.org/browse/FREEPBX-17209) to request a fix.