If Mongolia really did only export 3.44mt in April, it's clearly a disappointing number given the supply disruptions in Australia.
It also suggests that MCC is on a 1.0-1.1 mt pace for Q2 (using your formula of 10% share of Mongolian exports for MMC).
I think MMC is going to miss their 4.5mt annual guidance, especially when you consider that Australia is probably coming back online in a big way at this point, and will likely take back lost market share.
This news couldn't come at a better time, especially given the relative strength of the stock in the last 2-3 weeks.