Ooff, this seems a bit sketchy. We recently looked at GA runner alternatives and decided on https://avrea.com. See if you have a better experience with them :)
Since they have a /pricing page it would seem their business is not to make it easy to self-host but in fact to make people pay for the cloud version instead.
Why are people so hostile towards BSL? Paying/asking money for great products is fine and if the product's source code is in git, the better.
Not everything has to be _free_. The major benefit of OSS for many is that you can read the source code. The major benefit of paid SaaS is that things just work and you pay for that. BSL can be the perfect combination of these.