Was I right that it was the timer?
Cannot say you have to do more troubleshooting.
You may have 2 problems.

I cannot find a wiring diagram for this unit so am doing a bit of guessing.

First I would check the heater to see if it is grounded.
Check the heating coil.
Unplug the unit and both wires to the coil.
Check it with a meter, should be around 10 to 12 ohms.
Then check from each side of the coil to the case/frame, both should be infinite ohms (open). If not the coil may have sagged or broken and is touching the case. This can cause it to run on whenever the door is closed.

This condition may have blown a thermal fuse (Item 7 in Section 3).
With the unit unplugged remove both wires from the fuse and check it with the meter, should be 0 ohms. This fuse kills power to the motor.
The most common cause of this fuse blowing is a dirty/clogged vent system so check/clean it.

If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.

There is a good STICKY at the start of this forum about it's use.