Because there wasn't a coherent process in place we cannot know that any balls in the game were or weren't tampered with.
1) It is clear that the gauges used by the nfl were cheap and not calibrated. When the allowable PSI range is 1 PSI having gauges that varied by ~.4 psi, is a total joke.
2) No process to record ball Pressure, in this case Anderson said he "remembered" the unrecorded PSI of the balls used by the Patriots and Colts that were submitted, that would be 48 balls, this of course is nonsense.
3) Wells took Anderson's recollection of the PSI of 48 footballs at face value but not his recollection of which guage he used, yeah no agenda there boys and girls.
No set of initial conditions for the balls, no baseline. Are balls being kept at 72 F, coming in from the bus at 47 F.
Here is a video from the 2013 season showing the pregame ball acceptance process
http://mmqb.si.com/2015/01/22/deflategate-video-how-nfl-officials-check-game-ball-pressure/
IF the PSI of the balls have to be within 1 PSI and this is CRITICAL to the Integrity of the game does the process documented in the video look adequate?
The inadequate process and correcting it should have been the focus of the Wells report not smearing the Greatest QB in the history of the NFL.
But that wasn't the report that Wells was paid to deliver. So it wasn't the focus of the report.
The range for ball PSI should be increased to a reasonable level, say 11 to 15 psi with proper process and measuring equipment in place combined with NFL supervision of the balls at all times no team personnel involved at all.
Remember Brady went 50-64 in the 2nd half of the Colts game and during the SB, it is fair to say he is comfortable with balls inflated to 12.5 psi.