If you wish to discuss the custom programming of an importer that fits your needs, you can email me privately. My current rates for custom programming is $100 USD per hour. That’s not a simple thing to do. The data for the plugin is split across 3 database tables, one for sheets, one for tasks, and one for signups. So, it’s not a simple 1-to-1 mapping of data to database table rows.
Best way right now, if they have lots of games and need pretty much the same tasks/items for each game, is to create a sheet with all the tasks set up, and then just copy that sheet as many times as needed and change the title and dates as needed.