Other than a few VERY limited exceptions, the band generally does not like people present for sound checks. So getting to see a DT sound check is a very rare experience.
As far as getting to hang with the crew, I am not aware of any such package. However, you might mention to the band (especially JP) during the meet and greet that you are very interested in that. If any of the crew are then free between the M&G and the show, or after the show, they might be able to arrange for you to chat a bit. Not sure. I do know that those guys are all very busy, so try not to be disappointed if you ask and it doesn't happen. But I'd say that is probably your best bet.