Hi Magda,
this is a typical behaviour for long, flat surfaces. Tiny errors add up.
Did you delete all components before you started and use Exif Grouping?
If that does (or did) not help, then I would create a few Control Points along the water edge (if you have that), turn them into Ground Control Points and manually copy the X and Y coordinates into the “should be” fields and set the Z value (height) to the same (e.g. 0). Then you need to delete all components again and re-align and hopefully the surface is as it should be.
Can’t help you with importing calibration parameters but you should be able to find something here in the forum…