I’m sure Cinnamon bark oil would kill as much good bacteria as it would candida. Its a very harsh oil and would not recommend it internally. Cinnamon oil can cause extreme gut irritation/inflammation(internally). I have done a drop(diluted) in the past and I would never do it again. With a topical infection it would cause too much burning and inflammation. It might be worth a try for a oral rinse.
Do you have the study/article? Curious with how they did the study and the results with lavender?
The problem with some of the lab tests is that it doesn’t show how much damage it can do to the good flora. These lab tests are very limited because they are done for such a short period of time. Some of these substances might be really effective for candida for a few weeks and then end up being ineffective after a month. I wish they would do more long term lab tests with anti-fungals to see how the candida adapts/resilience towards the anti-fungal. The lab test may just give us a indication of what it is capable of doing but no definitive long-term results.