devtrackers.gg
You know that the DRG devs hate Diggy Diggy hole right? (you get muted/banned if you write it in discord chat)
So it'll never get added. The reasoning is that it's not a DRG song, it's from Minecraft and they want DRG to have it's own identity.
Nono, absolutely not hate. I adore it, personally. :D
It's simply as you say - Diggy Hole is a Minecraft thing, AND owned by the Yogscast, so we got no rights to it. And yeah, likely some mods on the discord just blanket-delete it...we get a lot of it. xD