You wont know until you try but I run material infinitely better than that and get about 10-12%. That trim is probably in the less than 5% range if you are picking out the nugs. Running with the nugs I bet it about 10-12% THC and no extraction is perfect so 10% would be your absolute ceiling running the nugs.
You are extracting not synthesizing THC. That bud is crap. No way it is even 15% THC. Thinking you are going to get 15% yield with material that is less than 15% THC is plain stupid.