Without anything else to use, the Odyssey G70B profile is the only one on your system that means anything.
The entire purpose of any profile is that it represents the color response of a given device at the time the profile was made, whether it's a monitor, digital camera, printer, projector or scanner. This so the OS and ColorSync know what the color range and gamut of that device is.
Very literally, any other profile on your Mac has nothing to do with your monitor whatsoever. They're just general hunks of Lab that do not in any way represent your monitor's output.
As far as the Odyssey G70B profile goes, that was pulled from the monitor's firmware and the OS set it as the default. It's only accurate (sort of) if you leave the monitor at the settings it was on as it came out of the box. Every manufacturer sets all monitor models to a common setting. They profile one of them, then include that profile with all monitors that are the same model.
Why only for the monitor's default settings? Because a profile is two things. First the calibration is done, which sets your white and black point color (5000K, 6500K, etc.), gamma, brightness, contrast and gain. Once that's done, then a series of color patches are read to create the portion of the profile that tells ColorSync what the color range and gamut is when created to that calibration. If you change any calibration settings afterwards (brightness, color temp, etc.), then the profile is meaningless. Anything you change also changes how a given patch color will display.
If you want to use something other than the horridly blue default of 6500K that monitor manufacturer's seem to be married to, and accurate color is important, then you must (yes, must) use a separate profiling option, such as X-Rite's Display Plus HL, or the Display Pro HL.
Don't bother looking for the built-in Calibration tool in the OS. It can't see the monitor and can only make a bad guess at what your monitor is doing.