Data tables are design-time objects, so runtime update isn’t supported.
If I may shamelessly plug my er, plugins, it may be a better idea to use Runtime DataTable to update a struct array from CSV on the server then replicate the structs to respective clients. Alternatively, you could put the CSV on Google Sheets and update data directly on GSheets and have your clients pull the new data from the sheet directly so you don’t have to mess around with replicating those structs.
iTween : Free, smooth, procedural object animation
easyCSV : Read data from any CSV and put them in an easy-to-access string map!
Runtime DataTable : Import and export game data to and from CSV or Google Sheets while your game is running!