It probably wouldn't show as dis. (disconnected) when a modem/router is actually connected to the line.... This homehub 5 has the gas discharge and the DC block capacitor inbuilt, similar to an NTE5:
Either way, the line will have -50V DC marking it as active, dial tone and also a VDSL signal present.
I couldn't comment on the Hub acting as an NTE, as I've never had that particular situation whilst faulting.
I don't know what is meant by your other comment though ??
All bog-standard VDSL broadband circuits will have those three symptoms you mention, present ............ it's whether those same three symptoms are reaching the end-users master socket, that matters.
The only way the CP/ISP's have to try and deduce this, is to run the remote test from the test-heads to the capacitor in the master socket.
It depends on what that test result returns, as to what the next stage of the fault process will be .... ie: appointed engineering visit or otherwise.