Sorry, a dongle can be a security device but can also be an interface device.
I've never used nexstar software and don't know if it will drive an eq5 or not. I thought nexstar mounts were Alt/Az mounts not eq. Years ago I remember using celestron drivers to connect to an eq5. I don't remember if they were
ascom celestron drivers or not. That was a long time before eqmod which is really to good not to use.