It really seems more likely that your front axle disconnect is bad, or perhaps a universal joint. Before you go too far, you should jack the thing up and check things. Look first at both axle universal joints to ensure that one isn't broken, binding, etc. You could test further by putting the TC in 2WD (engine running so that vacuum is produced to operate the axle disconnect) and the transmission in neutral, then shutting off the enigine. Now turn the front driveshaft by hand. If the axle is disconnected but the r&P are good, it will turn smoothly, rotating the right inner axle shaft where you can't see it. If the R&P are bad, you should hear it or feel it. Now shift to 4WD with engine running and turn it off again. It should now not be possible to turn the front driveshaft with both wheels on the ground, and with both wheels off it should turn one or the other. You could also just put it in 4WD and jack up the right front wheel alone. It should not be possible to turn that wheel if the axle is engaged.
If your fender-bender happened to occur on the right front, it may well have broken the vacuum reservoir that lives behind the bumper. This will result in no 4WD, and perhaps in your heater blowing only through the defrost duct.
