I don't believe GA. I believe he lied about the affair. "Comfort" and "console" are code words for sex. Especially for sex addicts who don't see it as an affair or a relationship it's purely physical for them.
He hesitated, hemmed and hawed. He may never said to RC verbatim "It was an accident that snowballed out of control." He might have said "it spiraled out of control" and therefore feels he isn't really lying.
GA likes to see himself as a hero who "consoled" a dying woman, when he was going over there for sex. I believe GA has a gambling problem, is a pathological liar and is a sex addict. The family is dysfunctional and the lies have lead to this fiasco.
It's possible GA hid CA's dead body because he feared ICA had dirt on him to blackmail him. Possibly molestation, child abuse on her or Caylee. Something is not right.