I know nothing about Greg Nagy and a cursory google search turned up nothing, so I suspect Herschel is being fed a can for an easy victory.
Should he win as expected, I suspect that his next fight will be a Strikeforce headliner event against someone who isn't very good but popular with crowd like Bobby Lashley or Kimbo Slice, in which case Walker will be thouroughly KOed but will walk away with a fat paycheck. That's really what all this is about. He can't be serious about pursing a full fledged MMA career at 47. He just wants to get in the cage, have some fun for awhile, get a big payday, and then get out.