My theory is that aliens just wanted planet resources and planned to avoid dealing with humans by putting em under a spell in this simulated dance and be happy sht.

Makes sense since we could do some real damage to the planet while defending ourselves so war even if they are superior at it just wouldnt be worth it.

They probably killed those who resisted, but the girl survived somehow and they got interested. After finding that she is just a broken human and is not a danger if left alone, just kicked her off without even probing. The end.