If the FOV Type for a game is "Multiplier" in the calculator, you can never use this value directly. You have to see the output for the Actual FOV which will show you the correct actual FOV value.
For some reason they assigned cl_fovScale 1 (70 actual hdeg 4:3) to in-game value 70 and cl_fovScale 1.55 (108.5 actual hdeg 4:3) to in-game value 110 and made it scale linearly between these points.
There's absolutely no good reason for this other than them being lazy with their implementation.