It seems she may be in collusion with the gang members, which is how she knows so much. If this is the case, she is putting her own career at risk, and the radio show. But if she knows so much, why didn't The Warriors just go to the radio station, take her hostage, and try to find out what is really going on, and see what else she knows?
You say the Warriors were not in a position to do that, but I am assuming that the radio station would not be heavily guarded and would very empty, wouldn't it?
Also if the radio host, was to blab all that in one night, the cops would have her under investigation, as she would be incriminating herself in gang activity, along with the gang who was feeding her information.
Why would the gang do that? Gangs do not give the media, progress reports on their activities. If a member of the media had gang ties, the gang would tell her to keep her mouth shut about what they do.
She's really just a narrator. But I'll play along.
One, the cops probably aren't listening in. Ever hear of pirate radio? She's probably not broadcasting on a major radio station and only broadcasting on a transmission that the gangs know about.
Two, gangs likely call in to hear about their exploits on the radio and bump up their own street cred. In this case, they're calling in to track the Warriors movements because the Riffs want them brought in or wasted and the Riffs are the biggest, toughest gang in the movie.
Three, the Warriors seem oblivious to the reports on the radio. And even if they had heard them, they don't have time to deal with it, they just want to get back home where they're safe.
Pirate radio station, not a mainstream, public one. Besides, based on the "coded" language, most people wouldn't know what she was talking about if they heard it.
The DJ is a means by which the Riffs disseminate information to all the gangs in the city. The movie predates Twitter and Facebook. So to get information to all the gangs they use the radio waves.
It is not a main stream station. You are not going to hear her say "we got all that stacks of wax for you cool cats" or "Be the seventh call at ... to win a pair of tickets to see Fleetwood Mac".
The Warriors have no idea where the station is and just want to get home.
Yet she plays songs like Joe Walsh's "In the City", which is pretty lamestream for even 1979. I kind of would have expected something with more black/latino appeal.
Back in 1979, it wasn't unusual for there to be maybe only 1 or 2 "cool" stations playing rock music. You maybe had 2-3 more playing the top-40 rotation.
I think the radio station in question is modeled after WNEW and the DJ after Alison Steele who had a hugely influential overnight show.
It seems hard to believe now, but overnight radio had a regular audience and many of the programs would put callers on the air, and some of them were regulars and became kind of known.
Gangs were phoning in, seemed to be a station that catered to "gang news" and music. Masai of the Riffs is listening in thru the movie, there's a shot of him sat with a pair of headphones next to a sound system.