I agree with Greg, and do not usually quaratine my invertebrates, especially ones with a record of being difficult to acclimate. Very little is known about these stars, and to date there have been no scientific studies of their diet in the wild. The only report of their diet is from the Baensch Marine Atlas, which reports they graze surface scum (Aufwuchs) from live rock. Like most marine invertebrates, these animals are fairly resistent to starvation, and 2 weeks without food is unlikely to have much impact on their health, provided they were healthy to start with.
Hopefully the conditions in your Q-tank are the same as those in your main tank and you can transfer the star with minimal stress. If conditions are not identical, then your best bet at this point will be for you to slowly bring the water conditions in your Q-tank into line with your main tank so that you can make the transfer by doing frequent partial water changes (perhaps even twice daily) on the Q-tank with replacement water being drawn from your main aquarium until the conditions are identical. In the meanwhile, if you are worried about the animal starving, perhaps you can add a well-established piece of live rock to your Q-tank to tide it over until the water conditions allow a transfer...
Good luck!
Rob