You could also set up Avahi or some other mDNS daemon to relay mDNS packets across the two different networks, so long as you can route the UDP/IP from one network to another you shouldn't need to create a whole bunch of TXT records.
I guess another advantages of going DNS besides not having to broadcast information is that you chose what you want to publish.
https://community.cisco.com/t5/wireless-mobility-documents/b...
However it is not particularly clear!
There’s a guide for setting it up with Avahi here: http://chrisreinking.com/need-bonjour-across-vlans-set-up-an...