I finished my Brrrgh Solo Speedrun, did it live as one of the forums said I could, but my stream cut off around the 6 hour mark. I immediately started recording from the moment the stream went down (lost 9 seconds of footage, but cogs were exploding during that time), and now I'm trying to piece the VOD and recording together, but the render time for this is over 12 hours, and I don't think my computer can handle that.

May I upload 2 separate VODs for the run submission to be valid? (Part 1 being the VOD, Part 2 being the recording)

Yes.