Regarding platform "competition", maybe add a 3rd chest for achieving an overall score. So even if PC doesn't make their platform goal, their score would count towards the entire-DAMP-community score, and encourage people to keep working on it, even if their platform chest is a fail.
So for this weekend, it could be a community score of 400,000. Say PC only manages 100,000, XB360 25,000, XBOne 115,000, they could still get carried by PS3 getting 40,000 and PS4 125,000.
But perhaps a better way would have been reach X points as a whole community, where at the result screen it was modified by number of players achieving no deaths (encouraging team play), and modified by difficulty (to play harder levels), e.g.:
1x immortal medal = 1 point
2x immortal medals = 3 points
3x immortal medals = 6 points
4x immortal medals = 10 points
then multiply by x2 for Threatening, and x3 for Perilous.
So a full team on Perilous working together could get 30 points, while a single solo Routine is 1 point.
If the Personal goal was 100 points, you could do ~4 Perilous full team runs, or 100 solo routines.
Would this encourage things along?