Earnest question, how is this actually legally viable?
Obviously the decompilation is open source, but those are usually distributed without assets, in some kind of builder that requires a copy of the game. And clearly the original game isn't open source, or else this decompilation wouldn't need to exist.
So... has the game been released free to the public without the source code? Has Lego or the original developer blessed this project? Or is the game just... in legal limbo or something where they feel comfortable taking the risk?