If that's true, I still think that's crazy. Whatever they say or promise before does change over time and there's a possibility they've changed their minds. I'll bet it's not exclusive to solo content at all.
The only reason I can think of why that can be true is because it's for testing right now so it's only for solo content temporarily, or to prevent queues from breaking (because apparently that's what NIN did at release?) assuming it's another DPS. Also temporary.