I believe there is a possible bug in tallying certain categories and not rewarding the badges correctly. For months, I received an Expert Trailblazzer badge, and the tally for writing the first review for approved places remained as 44. I have added many more places, especially shops and stalls in shopping complexes and markets. I also write an initial review and follow by subsequent visit. In short, the tally should be well above 50, making me a Master Trailblazer.
I am working on other categories to achieve the highest award.