I could see this being a decent middle ground concession, especially if it is noted that even after a certain pronoun is used, another is still overwhelmingly used. Once Ralsei has the "their" in the title, every other character aside from Asgore, who is unfamiliar with Ralsei at all and is literally unable to get a good look at him, still overwhelmingly uses He/Him, as does the menu/UI ("Ralsei gave it his all!" for his R-Action in the Flowery fight). This is why I'm so hesitant about this particular case. The instance of "their" being used in the UI for Ralsei only for literally every other UI instance, both before and after this, still using He/Him just looks like an oversight or it meaning to be vague. I also think "Their" in this case refers to the literal, titular Vine in the title, not to Ralsei. That's why I'm really wishing we'd err more on the side of caution until Word of God / Toby is able to weigh in. Mistakes happen. Things get overlooked. There have been several grammar and spelling errors already corrected since launch in this chapter. I just think removing it, for now, and giving it time to breathe and see where it shakes out is the prudent call. But I'm an overly cautious guy who likes to triple check everything X_x
But if we're gonna keep both in the info box, at least making it clear which pronoun seems to be the preferred one might be the way to go? Or maybe split it as "Primary Pronoun/Secondary Pronoun"? Or "Primary / Possible?" Maybe put They/Them with a question mark and note that it is at least a bit unclear as of right now?
(Edit: really didn't plan to chime in again, but I thought Cod at least had an interesting compromise if the consensus is to keep it, and wanted to try to be helpful and expand upon that)