When you say bind that infers templates are in use. You shouldn't have to unbind any networks when adding Sensors or any Meraki devices to combined networks (even when bound to templates).
If you need to update a template (or network) to include newer product types you can follow the steps in my slide deck here
Looking at what I believe is your network I can see the original template you had only included
productTypes:
"appliance",
"switch",
"wireless"
Whereas a newly created template will include all modern product types
productTypes:
"appliance",
"camera",
"cellularGateway",
"sensor",
"switch",
"wireless"
You can get this list using API get networks or get templates calls.