I've tried the below;
Rust Console 4.0
> o.grant group default smoothrestarterrejoinrewards.perm1
Permission 'smoothrestarterrejoinrewards.perm1' doesn't exist
> o.grant group default smoothrestarterrejoinrewards
Permission 'smoothrestarterrejoinrewards' doesn't exist
> o.grant group default smoothrestarterrejoinrewards.USE
Permission 'smoothrestarterrejoinrewards.USE' doesn't exist

Also checked in my admin tool and it is not showing in the perms?
The mod does seem to be loaded.

Anyone got any suggestions?

Thanks.