My first guess is they thought "camp stove", didn't actually look up the flow rate that model sucks down with both burners going full out, and therefore spec'd too thin a hose for that long length.
These are bog-standard valve fittings, ACME/QCC1 I'm guessing on your 10# bottle just like a BBQ tank, and Coleman style 1"-20 at your stove's regulator.
So if you're too far away now to take it back for them to make it right, it is trivial for you to DIY with OTS parts, just make sure to get a quality (nice fat) hose.
There are also adjustable variable-pressure high capacity regulators you can put on the tank side, usual practice for safety.
Note also extreme cold will greatly reduce pressure with such a small tank.
These are bog-standard valve fittings, ACME/QCC1 I'm guessing on your 10# bottle just like a BBQ tank, and Coleman style 1"-20 at your stove's regulator.
So if you're too far away now to take it back for them to make it right, it is trivial for you to DIY with OTS parts, just make sure to get a quality (nice fat) hose.
There are also adjustable variable-pressure high capacity regulators you can put on the tank side, usual practice for safety.
Note also extreme cold will greatly reduce pressure with such a small tank.