If anyone has an answer to this is really like to know. But what did they attribute their success to? Many have tried and failed to culture borrelia hence why we are in this mess. I'm not denying it I just couldn't find a clear statement of why their methods were better than the previously failed attempts in the preprint.
Anyways, I disagree with Dr Stricker. This is very good news
8 mL tubes of inoculated medium were filled to minimize the airspace present, thus providing a microaerobic environment, and incubated at 32 °C. Culture fluid was examined by darkfield microscopy for visible spirochetes weekly for up to 4 weeks. Cultures were concentrated by centrifuging the fluid at 15,000 g for 20 min, retaining the pellet and discarding the supernatant. For imaging, a small amount of culture pellet was resuspended in 50 μL 0.85% saline solution, washed and centrifuged again. The pellet was mixed with gelatin and then fixed with formalin for further staining.