He looks like a robo to me
Mind boggling to think what his cage mate might have been if they were labelled wrongly. If he was the bigger of the two, he'd probably been territorial over the food - that's the problem with pairs, one can end up being territorial and the other one not get any food.
They are mostly all fluff though. When you get chance to weigh him that should show he's a robo as they are much lighter than other species of dwarf - although you can get overweight robos!
He looks perfectly normal to me - and they always look a bit chunky as so much fur.
Great progress! Our robo would never take food from my hand. He'd take it if pushed through the bars - sometimes.