Bad Arolsen Archives will provide "family member" w/documentation of exact experience of Sawczuk family in Germany. Inquiry by immediate family is available free of charge. All one needs to do is to provide full name and any other spelling variants and exact birth date. The inquiry can be done by e-mail. The archives have upgraded their svce and response can be received via e-mail as well. Response can take as little as three days or asmuch as three months.
If Jan was on a separate German train, I would submit a separate inquiry on his behalf.