I am willing to help with the Sinnoh ID'S these are some I found with the /bgm command
Region ID
Sinnoh: 3
1004 Twinleaf Town
1005 Sandgem Town
1070 Lake Verity
1100 Look! Shorts Boy
1115 Battle! Trainer
1116 Battle! Wild Pokémon
1121 Route 201, 202, 219
I was trying to create a mod du muscia for Sinnoh if you could help me it would be great because even the logo I have but I can't edit the audio.ogg
I will keep updating my comment as I go through the adventure
here scan the Remake-style Music mod project logo for Sinnoh.