LTE box access when in passthru mode

so I have a Mikrotik device, and I added a LTE Mini for fail-over.

When I turn on the pass-thru on the LTE it works great, I have recursive routing setup, I can lose my main path out and the LTE device picks up and traffic is almost seamless.

But when I use pass-thru I lose the ability to access the LTE mini.

So I read that I should add a mgmt vlan and pass-thru vlan.

I set that up, and now my fail-over doesn’t want to work.

can I get a suggestion on how to setup a LTE in pass-thru with access.

Or can someone let me know the best design to allow recursive routing with pass-thru using a LTE mini, and still have access to the Mini.