It is simple. Find a cartographer, ask him to correctly map the earth pay him from wealth gained from changing everything everyone has ever known. Kick back and relax
How long would it take a single cartographer to do this? Is he or she supposed to work for free until the job is done? It really isn't that simple, and you know it.
The Earth's flat it's been flat since the beginning of time and will be flat forever, right? So it doesn't matter how long it takes. Surely after all these years and years of study* you guys can make a pretty solid case to employ a team
of cartographers. It's not working for free? You know how the world of business works don't you know? You get some quotes for the job, employ a firm then when they deliver you pay. It's like when you go to work and they pay you at the end of the month/week, they don't pay you every monday or before you've worked do they?
*perhaps take Bullhorns years of studies??
EDIT - Also, it seemed to be "simple" enough for you guys to conclude it's not round so why is it so hard to prove?