I just did some tests with an Analog Keys
Definitely use fine tune rather than detune! Detune parameter is a linear hertz offset and does not scale across the octaves, probably best used for modulation
Fine tune with a setting of -41 works for a -32cent osc detune, -41 also happens to be what my Virus global detune is set to
Ableton tuner is showing the same results for 440hz global tuning & -41 fine tune as it does with 432hz global & 0 fine tune