I should also guide them towards the correct, legitimate method to update the game. That would be using the Nintendo eShop on their Switch or a computer via the Internet Browser or Switch eShop. Highlighting the importance of purchasing the game and updates legally reinforces Nintendo's commitment to protecting the rights of game developers and publishers.
Resolved rare instances where using the Item Printer in the League Club Room would freeze the game or fail to reward the correct items. Understanding Switch File Formats: NSP vs. XCI
Regarding the NSP file and update links you mentioned, I would advise against using unofficial sources, as they may not be safe or reliable. Instead, focus on official channels for updates and content.