It lists 1993 as well though, the date of The Luxor’s opening: as for 2007, I don’t know when exactly the EST3 replaced the building’s original IRC-3 FACP, but videos up until 2021 show the system with its original message, implying that the EST3 wasn’t put in place until then or sometime before then (or at least the message wasn’t until then: who knows honestly).
Just because a large number of buildings in the Las Vegas area use that message doesn’t mean that SAFE Electronics, Inc. is the reason for it: anyone else involved with their construction could have proposed using it.