The maps don't even show that
What the neutron ratio shows is the neutron ratio - the "hydrogen" is inferred.
Unlike the Moon, where such an inference may have some basis, Mars is relatively carbon rich - We know that C is converted to C14 when irradiated, and that that C14 will then degrade slowly over time. Surface elements on Mars are more diverse than the Moon - There are a number of other atomic reactions which must take place on Mars due to Mars' relative lack of radiation shielding, due to its relative lack of magnetic field -
When you find a team describing Mars' radioactive environment, then you can trust their water numbers - not before.
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