Oh, come on, this story is good already, it doesn't need that overused "oh-but-we'd-known-...

I get what you mean since a lot of stories tend to overuse this type of trope and try to forcefully push it out of nowhere, but I honestly think it's alright in this case seeing as they kept implying that he's met her before and has been in love for a long time, so them having met before he became a paladin makes sense, they even said that she's the very reason he joined the order in the first place