This reminds me of Lambda School (in a good way). Will 10% of students' first year income be a sufficient cut for you? I assume a salesperson's first-year commissions will be much lower than future years.

Also, have you considered doing in-person courses at some point? It's less scalable, of course, but people may be more open to committing a portion of their future salary to a program they engage with in-person.

I see cool "learn to code" courses and bootcamps all the time. I haven't seen the same for sales. Looks like you are well-positioned. Excited to see where it goes.