A couple of observations
1) Thomas is a German soldier. What would a young German soldier do in 1945 when the war finished? Well he'd most likely think that he'd soon be treated to a hasty execution. So to avoid that he changed his appearance and became a jew by getting a jewish ID card with a photo that could pass for himself. He did the concentration camp tattoo himself in the DIY style just like they were done at the time and just how simple prison tattoos are still done today. Had he been a real jew from the KZ camp, he'd be a lot more malnourished and skinny as the Nazis did not feed the jewish prisoners a lot towards the end of the war. Also he'd never have the photos that he has in his wallet from before the war as those would have been confiscated had he been in a concentration camp. Those are his own photos that he just put in the jewish wallet/ID as a place to keep them.
2) Lore has her mom's disease (it's hereditary) as she saw her mother's legs shortly before she died. At the end of the movie she notices that she herself has these same symptoms and thus knows she'll soon die. in despair, as she can not tell anyone as she doesn't want to scare her siblings in case they have it too, she makes the scene at the table and smashes the porcelain figures.