I wouldn't if I was them. Nothing against Rodney, he is something of a legend in this town and his presence has always given KROQ cache (now known as "street cred" for you young'ns), but he is inextricably tied to the LA music scene of the 70's and 80s. Not that he hasn't brought other bands to our attention since then, of course he has, but the key word in Alt 98.7. is "Alt". Of course, they are implicitly saying that they are the alternative to KROQ. The challenger to KROQ that everyone but KROQ wants to them to have. Bringing in Rodney would be the equivalent of saying "we want to someday be KROQ, and we're not there yet, but hey Rodney is in the house!".
Besides the average 25 year old who listens to both KROQ and Alt 98.7 has no idea who Rodney is, and why should they?