it is very confusing
it probes at at Y45 = 31 + 14 = 45
you specify the area with M557 that is actually being probed in real coordinates.
but you have to keep the offset in mind
your initial offset did not work because
M208 X0 Y0 Z0 S1 ; set axis minima
M208 X190 Y210 Z200 S0 ; set axis maxima
M557 X5:185 Y5:205 S20 ; define mesh grid
in order to measure at Y5 it would have to move the head to y-26 which is not allowed. Y0 is the minimum per your definition.