I had the advantage of experience: I ran into the same problem several weeks ago.
When preset hiding a column, the data from this column is not downloaded from the server:
At this point, there is no workaround. The column with the rowid must not be preset hidden. (But you can hide it using the user-facing “Hide column”.)
We may create a general variable for the rowid in formulas / buttons (something like {_id} or so). But there are no concrete plans at this point.
