an offsite poll would be ideal, I’ve seen many over the past that might work although I would have to leave that to you, . plus I think you would be a better judge than anything I could suggest.
~ The ranking or winner selection was supposed to imply if there was a tie or discrepancy, that one or the other methods should provide an alternate winner.
The idea although in rare cases each might choose a different winner, is if 2 or even 3 of the Choice categories tied then one could fall to the next winner in that category, with (Epic) being the final judge in the matter.
Each category will have to have certain weights though, like Jammer’s Choice outweighs Community etc.
This might seem complicated but will work, say all chose the same winner, then 2nd place would come from Jammer’s if those matched the Community’s Choice then it would fall to the Community’s Choice’s 3rd etc. etc.
Choosing these winner’s & Final Judging should fall to Epic on all circumstances. We don’t need to see the inner workings we just need the final results. might choose to name the 3rd place at times deferring to the lol ‘better’ judgment of the Entrants & the Community for 1st & 2nd, plus he likes weird stuff . (that’s a joke, ) 
~ As far as linking 's stream, although no one can be completely impartial, is honest and doesn’t pull any punches, that’s the reason I always try to catch his stream. but the game jam entrants would be partial, rather they thought so or not, and might show just the good things and leaving out any mistakes, errors, or bad parts, etc. that might show up, although posting one’s own videos isn’t a bad idea, but should be an option.
Having a video of 's stream to use as a reference, one could choose the ones that would most interest them and be their choices then they could download and try out the games to finalize their choices. The whole idea here is to streamline the voting process and this allows more to see the entries without spending a couple days playing them.
(shamefully I must add, I haven’t done much in the way of videos. I barely have time to upload a Screen Shot most of the time)(although it is something I must move up my To Do List)
~ I have to admit, when I first started, getting a monthly sub code from participating in the Game Jams was an excellent incentive, it helped me defer personal assets to where I needed them more rather than investing them into game development. Although after calculating it one time I discovered a made less than some child in a sweatshop probably did out of the deal. lol
But even then I had started to realize the true reason for participating in Epic’s Game Jams, they were Fun, a great learning experience, and was great to see what fellow Entrants came up with and it’s great being part of the community.
What you take away from participating in the Game Jams is priceless.
ps: forgive so much text but had to try to clearly explain it all
** just remembered the stream earlier today, get Canon (Pence) to make up the rules, that’s what he’s there for. lol (pls don’t sue me Canon) 