Here is an experiment.
All sets close to fatigue, he'll go to fatigue if you want
BB press, 10,8,6 or Hepburn style, up to you
BB squat, 10,8,6 followed by a 20 rep back off set
SLDL, 2x10
Pullover to fatigue
DB row, 2x10
Chin-up pavel ladder style
DB bench 10,8,6
Weighted dip to fatigue
BB curl to fatigue
Farmers walk, BW to fatigue.
Do this every day with the aim of achieving some sort of progress in either number of rep's, kg's or ultimately both for the next three months and then report back.
A week Before you start eat a lot and rest, don't do anything.
72 hours before you start, use the "protien surge plan"
stock up the fridge on quality proten items such as soft boiled eggs, chicken breasts, swiss cheese, sirloin burgers, and would put all of this in a large tupperware container in the fridge and during the day snack out of it, at least every eat 2 eggs, or one of the meat items and then at night, would get up and eat as well.
In addition, eat regular meals, usually big salads and tons of fresh vegetables and maybe some brown rice.
take a high fiber supplement as well.
This worked especially well when I had been training real hard for the previous 4-6 weeks and had hit a plateau.
The results, solid muscle and strength gains in the weeks following this eating plan.
Let us see if overtraining is real, for a seasoned or mature trainee.
I doubt he would last one week.