Cake-VPN VS passepartout-app

I am now starting to understand the connections better and find the implementation of https://github.com/ashraf789/Cake-VPN a lot clearer. Only thing I can't figure out now is that I'm now loading an AAR file of open-vpn that I previsouly bought from Codecanyon. But the "Cake-VPN" apparently does not work with the functionalities within that AAR library.

I've been looking for the past days for a solution to get NextDNS and ProtonVPN seamlessly working together on my iPhone and found several workarounds, but none of them worked or worked stable enough. I prefer the advantages of NextDNS over Netshield. Then I remembered I purchased Passepartout quite a while ago (available in the App Store, also for iPad and Mac) and since it's a very user-friendly, flexible OpenVPN Client I expected it to have a possibility to enter custom DNS server, so I would be able to use NextDNS for parental controls et cetera instead of ProtonVPN DNS servers. I started fiddling, but to no avail, unfortunately I still had no DNS-resolution. I mailed the developer of Passepartout and got a reply within the hour pointing me to Github, to this closed issue: https://github.com/passepartoutvpn/passepartout-apple/issues/171#issuecomment-786809247. It works flawlessly and as I already had ProtonVPN configured, I only had to add an NexDNS ip address to the config, and reconnected and my problem was solved!