Pretty much the same.
Create a session with a friend both be on the main menu. Then both select card pop and you’re done. You’ll both get a random card.
With a lot of luck you’ll get one of the 2 rare cards that were exclusive to the game.
You can only pop once with a friend until you popped with 15 other people after. After that the first ID is overwritten and your friend will be seen as new.
Well officially you already waived your warranty by opening it yourself. So even sending it in Nintendo might noticed you already did that and won’t do anything about your issue.
Doesn’t it work at all anymore? Even connected directly to the screen?
Or maybe just the LED’s aren’t working (and with that likely the Sl and Sr as well) but still making a wireless connection?
And why did you open it in the first place? What was wrong?