Force all internet/VPN traffic over LTE?

I have a GL.inet MIFI LTE router running openvpn in a very specific scenario. I have devices connected to the WAN that I need to access from my VPN. That works fine, however the network that the WAN is connected to is very locked down, so they block DNS, websites, etc. meaning my VPN won’t connect. Right now it uses the WAN as priority, which means my connection is constantly bouncing between WAN and LTE. How do I force all my VPN and internet traffic to use LTE only? I’ve tried adjusting MWAN3 (which didn’t work because I don’t know what I’m doing), so I was hoping there was something simple I could do to just force the traffic to use LTE?

If you check /etc/config/network and /etc/config/mwan3, you will find the following settings

option metric '10'

A lower value means higher priority. So you can adjust the values of all interfaces. Set wan to 40 and set modem to 10, then all data will go to LTE.

Thank you for the help!