What happens in the above video is that we take all the values of a column (thus all items on each row) and distribute them over the rows in the new table. When I write it like this you might already understand that all values of the complete column being pushed into each single row, is not how to proceed.
The full explanation in the paid copy.
Explainer → Solution 2 ~ the complex one
This is the complex solution. When you can add buttons to a row, that goes faster. This method will on the other hand be a good teacher in the Coda List Logic. Once you see this solution, you also can deal with buttons in one table that manipulate values in other tables (like often is the case when you deal with planning and updates of all sorts).