That form for meshz doesn't use any x-,y-coordinates at all -- it just plots against the ordinal position numbers of the Z arrays -- documentation says from 1:N and 1:M but observation shows the above uses 0:N-1 and 0:M-1 instead.
But, even using the meshz(X,Y,Z) syntax that would be required to put an explicit axis on the plot doesn't solve the problem as meshz isn't enhanced to accept a time or duration class input -- when you try,
>> Y=1:3;
>> Z=rand(numel(Y),numel(Time));
>> meshz(Time,Y,Z)
Error using meshz (line 56)
Input arguments must be numeric or objects which can be converted to double.
>>
For something simple that you've shown here, the fix would be to just label the axis...
meshz(seconds(Time),Y,Z)
hAx.XAxis.TickLabels=compose('%d sec',Time);
xlabel('T'); ylabel('Y'); zlabel('Z')
produces
