Initial draw in simultaneous McMahon

What is the algorithm for the initial draw in simultaneous McMahon tournaments? In recently started Tianyuan Main Title Tournament 2014 there is a group with two 5d players. Other groups look differently. Is this a bug?

We try to slice across the strengths to build groups in a slaughter fashion… I think it could be improved but I’m not sure I’d call it a bug

I think the groups are randomly generated regardless of the ranks. There are 4 groups with two dan players, while the highest rank in the last group is 9k.