People complained until I changed my mind, and now there's a new plan:
We will do Mythic+ on Tuesday, as originally planned. We will likely only have the people for 2 groups, but if you can put together 3 that will be great. I will not be there, so we will do another group on Wednesday for those who either couldn't be there Tuesday, or who weren't able to be in a group on Tuesday.
The winners of the competition will be the players that can complete the highest Mythic+ Level in a full guild group before the raid on Sunday. So if both groups get through level 2 on Tuesday, your group and the new group make it to level 3 on Wednesday, and then you use your keystone with a completely different guild group on Saturday in your own time to complete level 4, then the members of that group that completed level 4 will win the competition, no matter how far they made it in previous groups earlier in the week.
TL;DR: I don't care how you do it, when you do it, or who you do it with (so long as it is a full guild group), the 5 people that completed the highest level by raid time Sunday win.
*Completed* does not mean beat the timer, but only means beat the last boss.
The Reward has changed as well: each member will receive 1,000g PER LEVEL COMPLETED. So if the winning team beats the last boss on Level 5, each member of that group will get 5,000g.
-Fright