Hello @mykola_strata
In this case you are not comparing the models but textures, basically.
It looks like over the water part quite big triangles were created. You can try to use bigger Large triangle removal threshold settings under the Unwrap settings.
Generally it is set to 10, but you will need to set it to higher value:
Also, as you have the unwrap already provided, you will need to make a new unwrap and the align the model again.
