Looks like all those settings in Helix and BH re: MIDI setup are good.
So, just to get this straight - MIDI Commander shows the button press from the Helix. Correct channel, too?
Then the MIDI log in BH is a bit puzzling. Did you scroll the log window down to see if there were any other messages? (And I apologise in advance if that sounds like I'm asking the blatantly obvious...) The reason I'm asking is that the RCT6513W87 device, I when I googled it, appears to be the tablet itself.
When you go into the setlist, is Android ever asking you to allow a connection to another device? Like a "Line 6 Helix" or a "2x2"? I'm guessing not - what is showing in the BH MIDI log is only the BH is talking to the tablet's internal MIDI, rather than an external device.
Try to force the issue by opening up the BH MIDI status window. If the big button is green and says "MIDI Running", press it. It should turn grey and say "MIDI Stopped". With a grey button, press it to activate MIDI. At this point, Android should ask if you want to allow access to one or more devices - one of which should be your connected device, either the Helix or the 2x2.
If BH can't ever find the external MIDi device, but MIDI Commander sees data, I'm at a loss..
What Android version is the table running? 6.0 (Marshmallow)? My experience with BH starts with Android 7, so I don't know if what you are seeing is normal. Maybe Arlo or another Android 6 user can comment on expected behavior in this scenario undrer Android 6.0?
It is also possible (though unlikely) that the Android port running on your tablet has a buggy MIDI implementation. But MIDI Commander sees data from the Helix.
Hmm... Try rebooting the tablet and going into BH without ever going into MIDI Commander. Is the BH MIDI log showing any other data? Is it asking to connect to the external device?