If you purchased the export pack when it was active (roughly between 2009 and 2014), you can still redownload the tracks on the same console family (e.g., from Xbox 360 to Xbox One/Series X).
It is not possible to purchase a new export license or redeem a new code for LEGO Rock Band . The licensing agreements officially ended years ago. Lego Rock Band Export
When active, the process required a unique code found on a flier inside the game case. If you purchased the export pack when it