Inside of Washing Machine smells horrible. How to fix?
First, let me say, you are far from the first person to have smell problems with washers, especially front-loaded ones. This has been the topic of many conversations resulting from home inspections and with concerned customers. I have had followup consults with factory reps, appliance repair specialists and the like. 

The most common problem seems to be with the rubber sealing rings at the door. Water sits in the folds, mold grows in the folds and is untouched by the "washer cleaners" that are currently on the market. Wonder why they are so popular? some folks have been able to manually clean these areas with bleach and many rags. Others have had to have it replaced then keep it clean before the mold takes hold again. 

Any closed reservoir can harbor mold and usually does. If you cannot access them to clean the mold out, that part usually has to be replaced. The other problem is if small amounts of water sit in the bottom of the unit and don't get expelled. this is easily treated with flushing cycles with bleach or cleaners.  

Before you completely give up on the unit, see a Bosch dealer with a good service reputation. Several models from several manufacturers have been recalled or service bulletins issued for exactly the problems you are having.