[Jared Russell]

Another lower-tech option would be the following:

I am reasonably certain that the FIRST website currently publishes the actual match start times with minute precision. Assuming timestamped video (if it isn't timestamped, you would need to manually align the start time to a known reference), you can use these start times to split the video (worst case :59 of dead air before the match starts). If there is clock misalignment between the published start time and the video time sync, you would very quickly (once per event) calculate the offset.

You could also use this system in conjunction with an audio/visual classifier so that your algorithm knows which sounds map to which match.