I THINK I understand your question. So let me take a whack at explaining the situation (I apologize in advance if I have misconstrued your point.)
As far as dividends are concerned, there is no difference between a naked short and a borrowed short. When it comes time for dividends to be paid, the amount sent to a brokerage firm is the NET amount of its longs minus shorts. Internally each brokerage firm debits short-sellers and credits long-holders. The brokerage firm wouldn't care about whether the shares were shorted naked or borrowed as far as dividends are concerned: either way the short-seller is out the dividend.
A firm which is net short is debited cash at DTCC.
To take an example, let's say a company declares a $1.00 a share dividend, there are 10 million shares outstanding, 1 million borrowed short, and 3 million naked short. (Let's set aside whether this situation is possible; I doubt it, but the principle still holds.) The company is paying out $10 million. Period. Let's say Merrill Lynch holds 3 million long and 2,000,000 short. They will be credited $1 million. Internally, in addition, Merrill will debit its short customers $2,000,000 and credit its long customers that $2,000,000 to make up the difference. Let's say that of those 2,000,000 short, 500,000 have a borrow and 1,500,000 were naked shorted (highly implausible, but it works for example purposes). It makes no difference whether those shares have a borrow or not; the short customers are paying the long customers.
In fact, on a really hot borrow, some of the borrowed shorts will start to fail. If that hot borrow pays a dividend, it's tough luck for the short-seller: first, he will get debited the dividend, then he will get bought in.
