Guess the hat colors - Riddle 4

I'm probably missing something, but I'll put out my current solution to try to think through if I'm missing anything. Easier to do that while explaining.

First things:

Using this:

However, at this point we run into a slight problem:

In conclusion:

I think the answer is:

Reasoning:

Based on statement #1:

An alternative:

But the problem is:

For B to positively identify his hat, any of the following must be true:

Let's (still) start with Scenario 2:

Here's how I attempted to do it. Let's denote the multi-coloured hat as m, black hats as b, and green hats as g. Let's now consider a few scenarios.

EDIT: Scenario 3a has been update to reflect the correct answer as per @Guess Hat's comment.

SCENARIO 1

SCENARIO 2

SCENARIO 3

SCENARIO 4

Thus, I conclude that,

I believe that the solution must be

Reasoning is as follows. A sees two hats containing black, so the possible hat orderings she sees are:

For B to know his hat colour he must see:

For C to know her hat colour she must see:

Now D knows:

OK - now that I understand that the competitors already know the number of hats of each colour that are used in the game I will try again.

Because there is only one multicoloured hat and A can see only two hats with black in them, there must be at least one green hat. So the possible sets of hats are some orderings of the colours

In each of these sets, there are 12 possible orders the hats could have been given out. I have drawn them in the following table. The first column is the order number (so I can reference them below), the 2nd to 5th columns show the hat colours of A to D respectively, and the 6th to 9th columns show if the respective comments of A to D are impossible (x), possible (o), or known before the previous players comment (b).

With reference to top half of the table. For the first set:

• orders 1,2,3,4,5 and 6 are impossible as A's statement would have been incorrect.
• orders 7 and 8 are impossible as B would have known before A's statement.
• orders 9, 10, 11 and 12 are consistent with B's statement but
  • 9 and 10 are impossible as C can't choose between two colour choices.
  • 11 and 12 are consistent with C's statement but
    • D cant choose between two colours so both are impossible.

With reference to bottom half of the table. For the second set:

• orders 1,2 and 3 are impossible as A's statement would have been incorrect.
• orders 4,5,6 and 7 are impossible as B can't choose between two colour choices.
• orders 8 and 9 are impossible as B would have known before A's statement.
• orders 10, 11 and 12 are consistent with B's statement but
  • orders 10 and 11 are impossible as C can't choose between two colour choices.
  • order 12 is consistent with C's statement and now
    • order 12 is also now consistent with D's statement.

So in conclusion: only the final arrangement (12) for the second set of hats is consistent with all the players statements and the colours are therefore