His DMI did not change one single point so for there to be a decrease in GS the training increase must cover it point by point...highly unlikely but not impossible.
Still I would like to hear some sort of response from GM-JuicePats on this as he sounded so sure that the OP words was fact.
What the OP posted is indeed fact.
If your player did not receive training, an automatic report would have been generated for the BBs.
Since there is no record of such a report, there is almost certainly no bug.
NO ONE at this table ordered a rum & Coke 
 Charles: Penn has some good people 
 A CT? Really? 
 Any two will do 
 Any three for me 
 Any four will score 
 Any five are live