On the June Case Calendar it says that KC spoke about the smell on June 5th (way before Caylee went missing). Is this a mistake?
It's possible.
Dogs are not infallible, as we know from the Elizabeth Smart case where Search dogs were within a few feet of Elizabeth and failed to alert.
I could discount the alerts on the trunk if it weren't for Cindy's own startling comment about the smell on her 911 call, as well as Lee's statement about the car being intolerable while parked in the garage, as well as Yuri's Bond hearing testimony. That's just too much at this point, to ignore.
But do all of those things make it a positive connection to decomposition?
No, they don't. Forensics should be that backup indicator, but LE doesn't seem to be very confident in that, either.