You might be interested in Hack Club Bank (https://hackclub.com/bank/), which we built for our students at Hack Club after they kept having the same problem (but with smaller amounts of money).
Today there are hundreds of student orgs running on Hack Club Bank, a few larger orgs (one with a budget of ~$100K/year, one that just signed on with anticipated budget of $1M/year), and now Hack Club HQ itself runs on Hack Club Bank (our finances are also open source on it - https://bank.hackclub.com/hq/).
While the page on Hack Club Bank on our website is still focused on student-led hackathons, we've recently started support for nonprofits not led by students. Perhaps it might be a good fit for Ardour?
Today there are hundreds of student orgs running on Hack Club Bank, a few larger orgs (one with a budget of ~$100K/year, one that just signed on with anticipated budget of $1M/year), and now Hack Club HQ itself runs on Hack Club Bank (our finances are also open source on it - https://bank.hackclub.com/hq/).
While the page on Hack Club Bank on our website is still focused on student-led hackathons, we've recently started support for nonprofits not led by students. Perhaps it might be a good fit for Ardour?