[kolya1]

Don't forget to look at Romanian, Italian, or Hungarian survivors. There still may be some of them alive. Or Germans who were outside the pocket, e.g. people who participated in the failed relief attempt.

As for the Germans in Stalingrad, I think it probable that you may find more survivors among those who were captured in late November/early December 1942 at the time of the Soviet conterattack. Those had not already suffered from hunger when they were taken prisoner. Many of those who surrendered in early 1943 were already ill or famished (or, very often, both) and died in captivity. The death rate in captivity among them was far higher than the average for the whole war.

But I think you may also find recollections of veterans written in the post war period or mail (although, in the latter, you must be aware that people were mostly conscious of the activity of censorship and therefore were careful in what they wrote).