First off welcome to the forum.
Roaches have this thing about laying a bunch of little eggs and being the worm bin could make an excellent environment I would have to suggest cleaning out the bin and start with new bedding.
Try following these steps to see if you can get your worm bin cleaned and free of roaches.
First sort out your worms from the bedding. Use a five gallon bucket or some other type of bucket and placing about 4 inches of damp shredded newspaper in it. Drop your worms on top and leave in a room with a light on while you complete the following steps. The reason for this, your worms will try to go to the bottom to escape the light. As they run through the damp shredded newspaper they will basically rinse themselves off, hopefully removing any roach eggs which maybe attached to them. Basically a homemade worm bath
Remove the existing bedding and rinse out the worm bin well, taking time to be sure no remnants are left in the bin.
Add new bedding material to your worm bin.
By this time good chance your worms have moved to the bottom of your bucket. Take the clean worms and place in the refurbished worm bin.
Lastly as chemicals and worms do not mix, you could try some sticky roach pads around and or under your worm bin. Also since roaches do not like the light, you could keep a light on in the area you have the worm bin.
Let us know how you make out.