Again, it all depends upon how you define abuse. The Obama Administration is going to paint the worst possible picture of the conditions he "endured" during his "captivity". They are in the process of building a narrative of their liking. They find one piece of crap that sticks to the wall when they throw it hard enough, and then they build on that and keep going.
Democrats always overreach on things like this because like Rahm told us, "Never waste a good crisis", but it takes a great deal of finesse and skill to do it properly, and all you have in the White House these days are Porgy and Mudhead.....
Having tried the "we feared for his health/life" line, the WH pretty much has to over draw any abuse or hardships. They are the ones who started painting the floor and wound up in the corner on this, and it's pretty much the only way out for them.
Anyone who has dealt with Pashto knows it is going to be BS - and they were the ones holding him for most of the 5 years. Nasty sods who fight like hell and have zero idea of the concept of quitting, don't get me wrong, but the video of his release shows a lot of marks of respect for Bergdahl. Little things, mainly.
He was dressed all in white and the clothing looked very new, traditionally a sign of respect given to new grooms or the dead (I can relate to that convergence some days!). He was both clean shaven and his hair cut in the military manner - both things forbidden to most Pashtuns and nothing they would think of forbidding any other than an honored guest from doing.
But apart from a very few people, little people who can be readily ignored by politicians and the media, who is going to know this?
There will be problems, depending how he were kept. He's certainly going to have the shits for a few weeks while his body adjusts to the new diet - you've been there, done that when you got back into port on leave! If he was kept up in the mountains, which seems to be the case, he's going to have both heart and blood pressure problems for a while until his blood "thins out" again. After 5 years in a completely strange environment, fully immersed, he's going to have problems adjusting to western cultural norms and social cues again.