If you are selectively enabling Bonjour on your network (via Bonjour Gateway or another such method) then you will need to allow LabQuest Bonjour service strings. They are:
_vernier-data._tcp.
_labquest-rfb._tcp.

Note: Depending on your network configuration, the period at the end of each line may be necessary.

The Graphical Analysis App listens for the first string; Vernier LabQuest Viewer listens for the second string. The first is also used by Logger Pro 3 for Data Sharing.

Depending on the gateway setup, there might be some other operands at the beginning or end of each service string. For example, in the same format the Airplay string for an Apple device would be:
_airplay._tcp.

And Apple TV is:
_appletv-v2._tcp.

Look at those for reference. For instance, if your Apple TV is setup like:
_airplay._tcp.local.

Then you will need:
_vernier-data._tcp.local.
_labquest-rfb._tcp.local.

Somewhat related:
._ipp._tcp.
is used by the LabQuest 3 to find printers.  Although DNS-SD is slightly different than Bonjour (mDNS).

RELATED:
How can I access a Data Sharing source if my network does not support Bonjour?