I tried a few times for learning exercise. End result - couldn’t find a workable solution so looks like standalone server is needed and a shame I cant have one server doing multiple functions which seems to be where you are headed.
When I tried Docker, it felt like a bad fit as a platform as MiaB assumes it is in control of the whole machine and wants to control Hostname, DNS and Firewalls which all require adjustments to get going. Ended up doing so many modifications to the setup script, it didn’t really felt managable and ultimately felt too much trouble and I gave up.
As an alternative, I did tried a VM which worked much better - however I couldn’t find a VPS provider that can really do nested VM and so dead end as well.