Why they didn't get other fill in hosts who are familiar with the show such as Craig Ferguson or yes...Doug Davidson. ..is mind-boggling
Remember, this has been done before. Back in the early years, when Bob was ill, Dennis James hosted a couple of episodes on the daytime version as well, in addition to his regular nighttime gig, so this is nothing new.
As for Doug Davidson, I don't think his version was that forgotten, because Bob kept making fun of it until it was finally cancelled, and even called himself the "old host" of "The Old Price is Right" (with Rod being the "old announcer" and Janice the "old model", though she preferred that she be called the "original model" instead). Carlos (temptation1979ga, IIRC) had clips of those rants in his Video Vault, and I remember them well. (SN: Years later, Burton Richardson, the announcer for TPIR94, would announce some Barker episodes after Rod's illness and eventual death, as well as an episode where Rich Fields went down with a case of laryngitis.)