The grids must have the same AOI. When you go through the import link, it resamples to the same AOI for you, but it doesn’t do this with a manual import.
You’ll need to re-make the grids in Kingdom to match the same AOI & cell size as the existing grids. Alternatively, you could re-grid them in Velit, but the former option is usually best.
Delete any grids in the model without the same AOI as the Time grid in the model tree, as sometimes intermediate grids can be generated that then continue to cause problems.