The molecular weight of oxone, KHSO5*1/2KHSO4*1/2K2SO4 is 307.4 g/mol. The triple salt, contains two equivilants of potassium monopersulfate, so we're only interested in half of your value of 614g/mol... I believe I did the math correctly here. If I'm in error, please walk through the calculations in detail showing the error.

If you do the math for 100mmol alkene, you use 200mmol potassium monopersulfate. That would lead most people to use 61.5g if you were to follow your own math. However, if you notice in the write-up I recommend using ~72.7g Oxone. This is because even 100% oxone has already started to decompose. According to the literature references I've read, if your oxone is reasonably fresh, it's a good idea to use 10-15% excess above the value that you recommend.

Becareful with the math here, it's super-easy to make a mistake.