Inserting Pre-Formatted Tables as Placeholder in Slide Master

[Italiano329]

Hello - I have a pre-formatted table that I would like to drop into a slide master so that if the slide layout is selected, the slide is already there and they can just fill some of the cells within the table, which has 4 columns and 5 rows. I only want them to be able to use this table. I see placeholders for tables, but that allows them to create their own. When I copy/pasted the table into a slide master, this essentially creates a non-editable picture in the presentation when the layout is selected.

Is it possible to do this? Thank you!