I don't have an answer based on any existing building code other then to relay my experience dealing with my attic remodel.
I think the point the egress route is a secondary exit if the primary (door) is blocked due to smoke/fire. I would imagine if your door to the outside is in a different location than the stairway to the upstairs (main floor) you may be OK. If it is not "up to code" you may be able to work with your local building department/fire marshal.
We turned our attic into a bedroom and only had 1 exit (the main stairway). The only accessable windows that you could crawl out of where three stories above the ground (too far the jump, at least that is what the fire marshal said). We filed, and received, a variance from the city, it was contingent on the installation of inteconnected smoke detectors on all the floors.