One reason to not put up a huge buy order at 0.845 is that...

One reason to not put up a huge buy order at 0.845 is that others can then buy at 0.85 knowing what your doing.
Doing it the way they are now, they are accumulating at 0.845 with the concern in the market that they are not buying enough.
This means they can get as many shares as they want at 0.845 without steaming the SP up.
Don't forget that Manipur would have advisors handling this for them too.
They aren't sitting at home putting in small buy orders everyday.
If they wanted to, they could push the SP to $1.20 tomorrow and state in the media that they won't be dealing to Kin for less than $4. The SP would rocket up and they are stuck at 6%.
If they keep going like this, they may get 9% and end up selling to Kin for $6, maximizing profits.