Using Eero from old internet service as Thread router

I've just signed up for Spectrum internet and have the new modem and router. As I understand, the Spectrum router is not Thread capable, but I have a smart door lock that uses Matter over Thread and it worked great with the Eero as the main router/gateway.

I need to know for sure if I can keep the Eero connected simply as a Thread border router for the door lock's integration, but use the new Spectrum router for my actual wifi/internet.

Thanks