Maybe the noise is coming from the motor.
You could try taking it apart and spinning the shaft of the motor by hand to see if it squeaks.
Your model dryer uses motor part # 2200376
I would also check the screws that hold the rear bulkhead in place to make sure they are tight, #9 in the diagram.
Had one that gave me trouble once and it took for ever to find where the noise was coming from. Ended up being a loose bulkhead screw.