Instead of getting mired down in the somewhat baffling aspects of RK's explanation about how he located Caylee's remains, let's focus for a moment on what we KNOW to be TRUE:
No matter what lead RK to the specific area where Caylee's remains were--whether it was ESP or inside knowledge--this much is indisputable: He WANTED LE to discover those remains! (Surely there can be no other explanation for his phone calls to LE in August and again on December 11.)
I can only conclude that his failure to force the issue with Cain--by marching him back to the exact spot, if necessary--shows that either (1) RK wasn't positive what the bag contained or (2) RK wasn't certain himself exactly where the bag was located.
If the answer is (2), then common sense dictates that RK had nothing whatsoever to do with placing the bag there. It does, however, open the question of how/why he had reason to believe the bag was in that area--a strong enough reason that he called LE out to the site, hoping LE would be able to locate and recover the bag.
If the answer is (1), then he clearly had nothing whatsoever to do with putting the bag there; he had no knowledge of what was really in the bag; and he didn't want to pursue the matter in August for a variety of innocuous reasons--ordinary laziness, for example.
Regardless of all, or any, of the above, the indisputable fact remains that RK wanted LE to have Caylee's remains. In my mind, that makes RK one of "the good guys" to a greater or lesser degree. I'll continue to think of him as that until someone shows me positive proof that he is a "bad guy," and by "bad guy," I mean that he's covering up evidence relating to Caylee's death or her killer.
Personally, I find some of his story and explanations odd, but I think that's the result of his lame efforts to preserve what he can of his dignity and privacy--all of which would have been intact if he'd remained an anonymous tipster as he'd tried to do.