"I think that would be the biggest mistake in the club's history," said Guttenbeil, who played 170 matches for the club between 1996-2006.
"It would be an awful move. They are trying to change the culture there and I don't think Benji Marshall fits that culture."
The controversial way Marshall departed the Wests Tigers and his subsequent departure from the Blues raised questions about his commitment, Guttenbeil said.
"Benji Marshall is a brand in himself and I don't think the Warriors need that in their environment. He was a tremendous player in his own right but they need consistent players, that is what they are striving for, and Benji Marshall has never been one of those."
Former captain Betham also advised the struggling Auckland club to steer clear, saying Marshall's likely high pricetag would be unlikely to produce value for money. "I wouldn't imagine the Warriors would make a play for him in terms of how much he'll cost and the players they have got coming through."
The focus should be on developing Shaun Johnson and the talented playmakers in the club's junior ranks. Betham also questioned whether Marshall would be fully committed.
"He's said he doesn't want to play league any more. Why all of a sudden change your mind because something fell apart? He's got the [Olympic Games] Sevens coming up in the next few years - would he want to do that and leave the Warriors high and dry?" Marshall's form had already faded "hugely" in his last couple of years in the NRL, Betham said.
