Expedition Guide/Leader career path advice

I turn 30 this year and am having a “mid-life career crisis”. I work a professional office job (sales manager) and have climbed the ladder to make a very decent wage but have figured out I hate this kind of life.

I have completed 2 years of college using my GI Bill (business management path) so I still have 18 months of it left to become a course collector and switch careers completely.

My dream job at this point would to eventually become an Expedition Leader for an expedition cruise line. I plan on spending a full year doing courses such as:
- WEMT
- STCW
- ENG1
- RYA powerboat
- Swift water rescue
- Sea Kayak Guide
- AAI Mountaineering courses
- NOLS Wilderness Guide course

Many job listings I’m finding list a bachelors degree in biology, ecology, etc. or “similar experience”. Can I realistically squeeze my way into the industry with things like NAI Certificate for Interpretive Guides, and university extension programs in subjects like geology? Independent learning is something I’m passionate about, and going back to school with a change of majors is very unappealing.

Any other advice for someone in my position would be greatly welcomed as well!