Can you tell me where you are getting this course and at which school? Is it for example Capabel, Sagenn, Mondriaan? I never heard of Gilde Opleidingen, so I'm wondering where that is. It's clear that this isn't a good example of how an 'inburgerings' course should work. The best thing for you to do, seems to be talking to the boss of all these teachers or go to the 'gemeente' itself. You should make their boss clear that they aren't really doing their work.
To get a B2 diploma you should actually also study CODE II and CODE III. I'm an teacher in Den Haag where I give an intensive course. The books I'm using are CODE I and CODE II, whereafter they will do an exam at the level of B1. To get a diploma for B2 they will also have to follow the course in which CODE III is used. If I were you, I would really try to go to another school, where the teachers actually TEACH and where you will be given more time to complete the course.
You could make your school aware of the procedure that other schools (like ours in Den Haag) use (where more than 90% of the students pass the exam).
I guess that it isn't possible for you to follow lessons in another school (in another 'gemeente'), because of your work and the time that would have to travel. If this is not a big problem, I would really try to look for a better school.
Keep me updated and good luck,