Coaches do know if they lie about a player, scouts will remember that. If coaches don’t tell the truth that marginal pro player may never get a look if Kirk doesn’t say so.The "NFL Draft Prospects" allegations for instance. What motivation would the coaching staff have to make disparaging comments about a player's draft prospects? After all having players drafted in a good thing for the program.
Again, Wadley's comments are easily identifiable.
So coaches are only as good as their word. So yes some coaches may have said a player had attendance issues because they know if they heap on unwarranted praise that scouts find to be untrue, it will affect the ability of Iowa’s coaches to get another player a look.
So there is a incentive for coaches to be truthful. Players may not like it but you made your bed in your 4-5 years in a program.