Should I explain a solution to a problem that only existed due to a mistake in the fundamentals in a bachelors thesis?
If your advisor is an approachable person, ask them! Standards for bachelor theses vary a lot between fields, universities and graders. It may also be that your advisor is the only person who will ever look at the thesis (if at all).

Learning to ask higher-ups is an important skill to learn for your life which is sometimes not tought well in schools.

So, let me summerize my answer: Ask!