FRAMEO & ImmichFrame Journey & Help

Posting this partially out of frustration and to help guide others.

[CONTEXT] I have a Immich and ImmichFrame instances on my Proxmox hosted behind an OPNsense firewall. I connect to them outside of my network through wireguard or OpenVPN through a DDNS provider.

[GOAL] I have a bunch of FRAMEO devices i would like to do this with for various non-tech savvy family members. One of them is built on Android 13, and I was able to install ImmichFrame and WG Tunnel. It works flawlessly. (Wireguard android app would not be able to reconnect the VPN tunnel if my ip changed).

[PROBLEM] Unfortunately the other FRAMEO devices are android 6.0.1. I am able to install ImmichFrame on them, but Wireguard/WG Tunnel require android 7+. I tried using OpenVPN for Android which is supported, but i cannot get it to auto-launch and connect to my home network at startup. I could get Macrodroid to create an automation, but could not get Macrodroid to auto-start. The Android setting screen has an Always-On-VPN option, but it does not allow me to select OpenVPN.

[RESOURCES & GUIDES USED] ImmichFrame guide for FRAMEO: https://immichframe.dev/docs/getting-started/apps#frameo Immich Kiosk guide for FRAMEO: https://docs.immichkiosk.app/misc/frameo/ Webview guide for Android 6 devices: https://docs.demonwarriortech.com/Documented%20Tutorials/Immich%20Frame/Frameo_Setup/#frameo-troubleshooting

[NEXT STEPS]

1. Is there something i am missing about getting OpenVPN to auto-start? I am also not even sure OpenVPN will avoid the same problem i had earlier with wireguard, where it would not be able to reconnect if my home network IP changes.
2. The Android Device has a built in VPN option (PPTP, L2TP,Ipsec etc) but i am unfamiliar with them. Should i try it? Ill need to create this VPN option in my OPNsense ugh. Also the picture frame requires a pin lock screen if i use this option, which sucks. I'm worried that with this option, the picture frame will sleep and require the user to constantly unlock.
3. Is there another VPN app i should use?
4. Should i put together a VPN router to pair with these picture frames? $$$ and probably need to install/configure OpenWRT on these devices.
5. The one picture frame that came with Android 13 works flawlessly, but i dont know how to efficiently identify them ahead of purchase.

everyone's thoughts and advice would be appreciated!