Client to GW VPN behind BR1 mini

Is it possible to configure the BR1 mini with AT&T cellular WAN for client to gateway VPN connections? I have a Ubiquiti UDM SE Pro acting as my FW/VPN end point and need to grant client access to networks behind the UDM. This is normally a pretty straight forward setup but it appears that I am triple NAT’d and don’t have a routable IP address to point the clients to. Is there a work around for this?

Thank you

Typically I would use a FusionHub Appliance hosted in the cloud for this.
The BR1 would build a PepVPN to the FusionHub and then client access would be directed to the Static public IP of the FusionHub with port forwarding from there to the UDM,

Made a video about it here a few years ago: Setting Up FusionHub on Vultr – Martin Langmaid – SDWAN Architect