I don't have any idea about 1998, but judging by Kevin's admitted resentment over Perry's return in 1996, it's not outside the realm of possibility that he may have said some things at the time that didn't exactly leave him in good graces with Cain & Schon after Perry's return. Besides, in The Storm, Chalfant was hooked up with Herbert, Rolie, Smith & Valory - 3 guys who had nothing to do with Journey at that point.
Just because he was in a band with those guys doesn't necessarily mean that Cain and Schon were falling over themselves to work with them. If anything, Chalfant's always struck me as being Herbert's "golden boy," a guy Herbert thought he would use to finally de-throne his arch nemesis Steve Perry. I've never thought that Chalfant was "equal to" Perry as far as talent goes, but that doesn't mean he isn't a fine singer...But for Herbert to hold him up as some "Perry Killer" never did any service to Chalfant, because in reality, let's face it, Chalfant is no Steve Perry. The very fact that Herbert was pushing Chalfant at the time may have worked against him in Cain & Schon's eyes.
As for 2007, there was no way Chalfant was even in the running for that gig. Herbert had sent Cain & Schon the "Fly 2 Freedom" CD and it didn't advance his cause in the least. As one member of the band put it, they felt like the CD was just "dull...tuned down Journey covers that sounded like they were sung by Bon Jovi." It was also mentioned that Chalfant was older, less mobile and appealing on stage, and was "old news." So at least there's the scoop from 2007.
Listen, some people hold up Herbie Herbert like he is some golden god of all things Journey, because that's the image and legend he's perpetuated through the years, and that's how he wants to be seen. But just like anyone else associated with this act, he has his own agendas and politics and just like anyone else in this band, didn't always want to make the right decisions for the right reasons. But like Steve Perry, Herbie has been out of the limelight and his PAST with the band is how his legacy is reflected...and like all things in the past, the immediate truth and reasons why things did or didn't happen are distorted, exaggerated, or forgotten, and that's just the way it is.