Yeah, but there's no such thing as a "Superstars announcer". Superstars isn't even really it's own show. It's just a collection of dark matches. Like, they tape one at Raw, and one at SD. Would they really need a new one for that? I don't see why they would, when Superstars doesn't even try to be it's own brand, or have its own announcers.
This is a time WWE is trying to save money, so I doubt they'd hire someone new just for two matches, and even pay to flyt hem from Raw to SD, when they can continue using Lilian for the Raw match, and Roberts for the SD match.
It makes sense to me that they'd get rid of Lilian, who is probably being payed quite well, and get someone cheaper, to save money.