Your display has a small hole that you can see. I guarantee that there is another hole somewhere.
Possible solution. If it is really cold where you are, take the microwave outside and leave it for 24-48 hours. Kills em dead. We did this to our appliances when we moved from the House of Doom into our new house. We loaded everything into a U-Haul, left the door open but facing the wall of the house, and left it there for 24 hours. We wound up sweeping dead roaches out of the U-Haul from where they tried to run and froze. The new house had not had a single one.