I think all theories are great for different reasons, but I personally think the team is comprised of Locke, Macer, Buck and Tanaka. The White Spartan looks very feminine and it doesn’t look like something Romeo would wear, especially when you look at Buck(it’s Buck, no question about it) who wears an ODST-ish Mjolnir Armor. If Buck would wear that then why wouldn’t Romeo wear something similar?
But those are just my thoughts, would love to hear yours!!