Agree with the above posts about the airlock situation.
Don't assume based on a visual observation of a pellicle that you can determine anything about the yeast, bacteria, or assembly of microorganisms in a culture. Plenty of wild yeast (even among the saccharomyces genus) and bacteria create pellicles. Many other wild yeast produce similar flavors and attenuation as brett. The only way to know for sure would be to look under a microscope with the proper dye.
That said, not knowing what it is does not mean you cannot brew with it or produce something you enjoy.