When a dryer squeals there are three parts that are suspect but the most likely cause of a squeal in your dryer is the idler pulley.
The drum rollers can also make a squeak noise and the felt seal around the drum may allow some metal to metal scrapping.
The most likely cause of a squeak is the idler pulley.
Unfortunately this dryer has no lower access panel that you can remove to get a better idea where the squeal is coming from and with the front panel off you can't run the machine.
If the noise increases I'd recommend replacing the idler pulley first for this problem. I've included some instructions for changing the idler pulley in the image below.
If you're comfortable and confident in your do-it-yourself abilities you can change the idler yourself and save the cost of a service repair.
To remove the front panel you first remove the lint screen and remove the two screws located there. Then use a putty knife to push in and release to clips located about 4 inches in from the front corners. The top is hinged in the back and with the top up you can see the drum seals.
With the top up remove the two bolts holding the top of the front panel to the cabinet. The panel will pull out and up off the two lower clips.
I hope this information helps to resolve your problem and it you have any more questions then submit another question with additional details for further assistance.