Does my answering "Yes, possibly" to the question "Is it possible for me to smoke here?" count as making a forbidden act permissible?

There is no doubt about the prohibition of smoking, and allowing a smoker to smoke is an act of disobedience, because it enables the disobedient person to commit his disobedience. It also implies رضا (assent) to it and approval of it, which is contrary to what Allah and His Messenger have commanded regarding the obligation to condemn evil. The shyness that prevents one from condemning evil or leads one to permit it is blameworthy shyness.