With the ceiling fan, in my experience, vaulted ceilings are a PITA to run any kind of wiring through. You will most DEFINATELY have to open up at least a couple points in the wall and ceiling at best. at worst MORE than a couple as you'll need/ want a switch and fan control by the doorway which most likely will be on a wall adjacent to the wall that the vault angles down to, making a run quite fun. it can be done, but you willl PAY...
And seriously, don't have "my wife's cousin's sister's husband, who used to work as a janitor in a grade school" do it this is something that NEEDS to be run in conduit, especially if you're in the Chicago city limits, the codes are there for a reason and romex or some other non armoured wiring will pose a huge risk in the event of a fan motor failure. ALL wire insulation deteriorates, some slower than others, but have you ever worked on the old cloth insulation from old homes? The stuff will fall apart in your hands, imagine that happening in the sealed up ceiling in 20 years (provided you remain there) and just causing an electrical fire taht the inopportune point in time. stuff like that happens, if you're in conduit, you're shielded and have a strong layer of protection from a fialure and most likely a breaker will trip 1st.
Anyway, point of the rambling is, have a qualified guy run it in conduit. Crappy part is it will cost ya and be messy as you'll need to patch and repaint where the work was done.
Wiremold looks like poop, it gets the job done, but it ALWAYS looks like a hack job, even when done properly.
best to have it done right.
Good luck and let us know what you do.
Hope all is well BTW,