Dole whip is not exclusive to Disneyland. They have it at an ice cream place here called Lappert's and also at a frozen yogurt chain called "Fiji Yogurt" down the street from my house. So I don't see why Disneyland would discontinue it even if Dole stops sponsorship.
In the unlikely event Dole did end the sponsership Disney could continue selling it.
Anyone can buy the Dolewhip mix and it actually comes in other flavors besides pinapple.
I buy the mix myself and make it at home in my cuisinart soft serve machine.
the day DOLE WHIP is no longer being served @ Adventureland is the day MONTE CRISTO sandwiches are no longer being served @ New Orleans Square (until I see an actual Team Disney Anaheim memo stating "no more dole whip" its not happening) ... C J