Luis, I noticed the .NET folder on your Chrome bookmarks bar, and that set me to thinking about your original post comment of “I am thinking I need a query that calls two tables (player and games) with an .eq (child_id).” Unlike the Microsoft “ecosystem”, Corvid does not support writing queries with joins between tables. References are the way of getting at data from other tables in wixData query, as you are already attempting to do.
Your screen shots are helping me see the reason for the “Included Games field does not exist in schema” error. When you use include, it has to be a reference field in the collection that you are querying, not the name of another collection.
Also, spend time getting familiar with the array structure of query results with a console.log(results) line, particularly with how it returns the results of a referenced field. Given what I see of your collections, I think that you had the right idea except that you want to have include function be on season. In the .then section of the code you could then query the Games collection because you would know both the season and team of the child. The results of that query would be the basis of the schedule data that would feed the table. You may need to do some modifications so it displays everything that you want in the table, but you would be most of the way there.