It sounds like the parents, the GGF, and IR were all in fairly close proximity when little Deorr went missing. If the parent's "exploring" story is to be believed, it seems almost impossible for IR to be involved -- unless he somehow kidnapped Deorr without the GGF noticing, incapacitated him, and hid him outside of the 3 mile search zone -- all within the span of 10 minutes or less.
Since he was not far from the camp site, I am assuming the parents checked with IR and/or IR heard them yelling for little Deorr shortly after they returned from the 10 minute walk. If IR had been missing for awhile when the parents initially started searching and/or disappeared for quite awhile before LE showed up, it seems we would have heard something about that by now, from LE, the PI, the family...somebody. I think IR is strange and I wouldn't necessarily want him around my kids (if I had kids, that is), but I am not convinced he is involved in little Deorr's disappearance.