Maybe. Maybe not.
Evidence and actions of people involved (Big Red + D/D/S/S/C/P] suggest that whatever truly occurred was trivialized, marginalized and not anywhere near what the GJP suggested occurred.
Step 1: First of all there is some doubt that McQ acted immediately and that by the time he got JoePa maybe six weeks had elapsed.
Step 2: Even if McQ spoke with D and Dad that night, D and Dad both stated...nothing much to see here, but go talk to JOe
Step 3: McQ Himself says: I gave Joe a watered down version of it all out of respect.
Step 4: Joe testifies in 2011 , I don't know what you'd call it? I know this is out of sequence, but Joe's involvements was all of three minutes in 2001)
Step 5: C&S speak to McQ a week or three after Big Red talks to Joe. McQ doesn't tell tell them anything of substance (apparently/allegedly).
To this point, given the time delays and clear lack of information from the ear-witness, it is not unusual to perform some investigation on your own. We all do this. Its a part of "fact-finding" to determine what a next course of action should be (that is, unless, you truly do see a person being forcibly sodomized, or a gun being fired or something that is distinctly and clearly criminal...).
Their investigation concluded that tell Dr J was sufficient.
I can't really find fault in that position given what is known.