This is all from realitybbq. They say they asked the HG directly and these are their answers:
Holly:
Said she was already in talks with BB about going back
Here is a list of HG that said
IF they were offered, they would say yes:
Season 3: Josh, Marcellas
Season 4: Alison, Dana, Jun, Michelle, Nathan
Season 5: Dana, Holly, Marvin
Season 6: Howie, James, Janelle, Kaysar, Sarah
Very Likely to accept:
Season 2: Dr. Will
Season 4: Justin
Season 6: Beau
Likely:
Season 2: Mike
Season 4: Robert
No:
Season 1: Brittany, Cassandra, Eddie
Season 2: Nicole
Season 3: Amy, Danielle, Jason, Lisa
Season 4: Dave
Season 5: Karen, Lori, Will
Season 6: Ivette, Maggie
Undecided:
Season 2: Mike
Season 3: Roddy
Season 5: Scott