I find your post today, my apologies for my late answer.
I think the german governemnt in 1950, was afraid by this ruine….
When the US troop was in Bertechgaden this town was « a touristic historial tour for US troops » visit the house of hitler ect…
But after the us troops leave, the german government, not want that this town, became a nazis historical tour ……
For the german people it is very hard to speack about the WWII…..
I was in germany for my holiday 3 years ago, and I have visited Hambourg (my grand father was prisonner in Hambourg during the world war two).
I spock with several german peoples, and I ask her about information of the WWI.
I felt peoples uncomfortable, when you speack about WWII.
A german friend of mine said to me, It is not easy for a german guys to talk about this period, there is still a lot of taboo on this subject, I think you are in the same situation when you ask a french guys about the vichy governement.
I think the german goovernemnt destroyed this ruine for this raisons and for forget this periode.