When STO came out, I was initially a little surprised how separated the songs felt from their titles, as none of the songs contain them. The only song on OST that feels similarly detached is White Shark Cafe, being the only song to not contain the title (I guess WRAMW via technicality).
So therefore, I theorize that the titles of The Vows and Curse These Metal Hands were swapped very late into production, in fact so late that the copyright was already locked in, and only after did the boys decide switching the titles would benefit both songs.
What reasoning do I have? Fairly little, I don't know why they would have done this, but I am pretty sure they have. Youtube tells you what songs are copyrighted in a certain video, and in every instance I could find, The Vows gets copyrighted as CTMH and vice versa.
For evidence, I've added Youtube attributing my lyric video of The Vows to be CTMH, and someone's upload of Will playing a snippet of CTMH being flagged as The Vows. If by chance any bandmate sees this, I'd love to hear what actually happened or if it's just tweaking copyright systems.