Interesting calculation - both approaches have their validity.
Coach looked only at what a 43-101 could speak to - 60 m long x 60 m deep x 3.6 m wide from the one indicative set of holes.
You are extrapolating along much of the strike, 5000 m long x 300 m deep x 3.5 m wide. That is of course possible, but can be neither indicated nor inferred at this point.
That said, your approach justifies a premium on Coach's bare numbers. If Coach's numbers are worth $4 a share, and yours are $13, then we could probably take $1 of your figures and add them to Coach's $4 to suggest $5.00 as a reasonable market value, with a possibly or even likely trend towards your $13 figure.
I think the market will tend to Coach's figures at this time only because, even though our data at this point is superb, it is very limited. We are groping about in a dark cave. We have gold under our fingernails already, but there is a lot of cave in there - a big unknown.