Curious that they plan to seek damages through the Arizona based division of Lufthansa Flight Training - Airline Training Center Arizona (ATCA) as his training would have been overseen by the parent company in Bremen at that time. The reported decision to interrupt training would have been made in consultation with the Head of Training in Germany and although he held an FAA Airman's Medical Certificate, his JAA Class 1 should also have been influenced. Perhaps the FAA's transparent and more readily available records make the likelihood of a successful case in the US greater? And of course there is the obvious:
The families’ lawyers argue that compensation in air accident cases in the United States is usually a lot higher than in Germany.
There are many professional pilots flying today who have had their training suspended at some point due to either medical or performance concerns who have subsequently been allowed to resume flying in the interest of running the business - I would be surprised if Lufthansa Flight Training had their own interests in mind in this unfortunate case however.