As for the room where the explosion took place, sadly no. There is almost nothing left of the wooden structures in the area. What the Germans didn't blow up when they left has rotted away.
Aside from basic maintenance & safety (and the hotel of course), there has been no restoration work done on the structures within the Wolfsschanze. Which is also why there are no roped off areas, no tour guides (though you can ask for one). It's a memorial site rather than a museum, which I appreciate. Being able to touch the buildings, climb inside and on top of them, feel the claustrophobia of the dark tunnels connecting the rooms... restored places can't do that justice IMHO.
There is even a restored troop carrier on site, that you can pay for to take you on rides, but ironically it was broken down the day we were there, and under a tarp so I couldn't get any photos