The wasp/mage should have approached in a cut scene as you neared the house, then after you kill him, the queen bee should have done the same. With one or two bees killed, she would be annoyed with you, but should still give you the key (with no bees killed, she would have taught you a skill). With more than a couple bees killed, she gives you the key and tells you to get the hell out and never return.

You can get another key;
Lost Items - guide and directory of inventory files

or get past the door;
Teleporting Anywhere, via hex editor