Highly possible. Came from a creative firm that had the original video, the DTS track, a stereo track with the president speaking, and a bunch of ASS translation overlay files in the MKV. Unfortunately the vendor is now not our friends so to speak as our marketing group tends to have a fallout with every darn vendor they work with so can't comfortably go back to them for help.
Funny thing if I convert the video in Handbrake it still can't open in Vegas. However, if I run the video thru eac3to with the -slowdown I think it was command, it complains about the video but when I take the resulting MKV and the extracted DTS track and multiplex those back together, then have handbrake convert it, Vegas can open it. Problem to date is though I'm loosing audio sync in the final result so hoping for some advice on how best to deal with this situation.