It's showing you the vertical distance since the conversion setup selected is vertical. Switch it to horizontal and it will show you the correct value for this axis:
Converting from Windows does not necessarily feel correct for everyone, even though it's mathematically correct. There are many different ways to go about the conversions, the best is probably to base everything off of a game you are comfortable in, that have proper sensitivity settings for different aim levels.
If you don't have this, basing it on Windows is a good option. However, as you found out, the 360 distance for hipfire will be different based on the FOV. So a good workaround is to find one game that are converted from Windows that feels good, let's say MW3, and use this as the source for all future conversion, but then do 360 distance for hipfire and MDV 0% for scopes. For scopes you can never expect the same 360 distance, so they will with this setup still be based on Windows.