Zone 5 is eligible for a limited selection of Devils games that air on the main MSG channel, but they're blacked out of the MSGSN telecasts.
i.e. the upcoming schedule shows them getting the 10/20 Devils game on MSG
On the MSG+ app, "MSG Zone 5" is actually the same feed that Zone 1/NYC gets, while "MSGSN Zone 5" has alternate national programming whenever the Devils and Islanders are on, and also carries MSG2's Knicks and Rangers telecasts as there is no overflow feed for Zone 5.
Zone 1 is NYC and central NJ where they get everything except the Sabres
Zone 2 is Eastern NY where they pretty much get all the NYC and Buffalo teams
Zone 3 is Western NY where they get the Sabres and Knicks
Zone 4 is Monroe, Carbon and Schuylkill counties in PA and eastern Connecticut where they just get the Rangers and MSG's Devils games
Zone 5 is Central Connecticut and the rest of Northeast PA
Zone 6 is Northwestern PA - Crawford-Warren-McKean-W Potter
Zone 7 is Southwestern NY
Zone 8 is Litchfield CT
Zone 9 is Northern PA - E Potter-Tioga-Bradford
Zone 10 is Central NY, they get the same teams as Eastern NY, but the Sabres get priority on the main channel
"Zone 11" is MSG National