does this affect the ufc??

If station casinos go under, does that have an effect on the UFC? (same owners)

Does it have an effect?

Sure. If the Fertitta's primary business goes under it might change the way in which they run Zuffa. Or they might use Zuffa money to prop up Station, much as they used Station money to prop up Zuffa in the early years.

Will it drag Zuffa down with it?

No. They are separate companies, and Zuffa is still turning a tidy profit.