What worked for any access to youtube on app or browser, etc was doing the following 3 entries:
in the UI of instant.arubanetworks.com:4343 -
1. select NETWORK: ANY, DENY, DOMAIN: googlevideo.com
2. select NETWORK: ANY, DENY, DOMAIN: youtubei.googleapis.com
3. select NETWORK: ANY, DENY, DOMAIN: youtube.com
worked like a charm!
p.s.
i removed any of the entries that block streaming or youtube in the web category, app category or app sections. all i wanted was to have youtube blocked on the network. PERIOD