Answer: The fact that the vacuum hoses have come off should not have any effect on the fan switch. These switches do fail occasionally and when they fail the fan speed is usually stuck in the “Off” or “Low” position. Switches are available and not particularly difficult to replace.
The hoses will be a little more difficult to deal with. I believe that there are five hoses. If I remember my middle school math properly, there are 120 different combinations (5 factorial) of ways that you can plug these hoses back on to the control unit. If you have a lot of time, and a lot of patience, you can try all 120 combinations. Of course you’ll also need to record each attempt so that you don’t repeat the same combination. You could hire an assistant to do this recording, but it might be less expensive, and a whole lot faster to simply buy a service manual which will include the vacuum diagram. I prefer the factory service manuals. Sometimes you can even buy the vacuum diagram by itself. These hoses tend to get brittle, especially near the ends, which is why they probably fell off. If the hoses are long enough, snip ½” off of the end of each hose before you plug them back onto the control unit. This will assure that they stay in place.