I'm wondering if they are still making money and why they are out of supply of Bitcoin considering that there should be an inflow of Bitcoin since many gamblers are losing their money.
Correct me if I'm wrong but at least the excerpt of the article quoted in the OP does not say that gamblers are using Bitcoin in playing poker. They are making dollar deposits to the site and played with it but then demanded that the payouts be made in Bitcoin. So I guess the site is earning in dollars and then use a portion of it to buy Bitcoin for their patrons' payouts.
And also, the site is offering poker games, which means it has regular revenue coming from rakes or commissions. It is not like players in the site are going up against the house.