Bartholomew Roberts, saying "the committee got up and walked out on the experts" might be a bit of a stretch. If you go to 1:32:55 of the following video I only see one vacant chair on the committee and plenty of occupied seats at the end of Doar's (the guy with the 10/22's) testimony, granted it is hard to see left and right sides but the middle is full.
http://www.youtube.com/watch?v=Tw7pTX_kDEg
Although there were no questions asked of Mr Doar, noted to possibly be a first, it looks as if the majority of the committee was still there at the end of his testimony.
The article in the OP shows a tweet by Doar saying "they all walked out together quietly in the middle of my testimony" yet in the comments section he (assuming it is really him posting under his real name) says "Rep. Hausman couldn’t even be bothered to stick around to hear any of the testimony.
I offered to do the presentation again for her… her office declined."
While some my have left most of the committee seems to have at least listened to Doar's testimony.