Assuming playerID field is of type Single Line of Text (If data type is different then let me know. I will change query accordingly),
Try your query in below format:
Per my test, I could reproduce you issue on my end.
Seems that the character ' cannot be encoded correctly, try to replace it with " and remove the slash \. Also you need to change the Eq to Contains.
Here is my demo for you:
So, if you google for "SharePoint CSOM Large Lists", you will find plenty of examples -- but the gist is that in order to query a large list while staying within the ListViewThreshold, you have to set a RowLimit, so that SharePoint doesn't try to scan the entire List in fell swoop, it will only scan the number of items specified by RowLimit. But of course, ...