You will find there are TG's that are not listed. The RR database is the best resource in the world, but depends on us as users to help keep it up to date.
Best thing to do is leave your scanner in open mode and ... wait.
I have found TG's that were not in the database in System 6/7, 8 and 10 that way (most were jail ops, Public Works, and training - the Heavy Equipment trainer on System 8 (6160/6192) is hysterical).
Depending on the scanner(s) you have, a discriminator tap on your radio, and Trunk88 might find a connect tone if you really need it for something.