iTunes File Size Problem

Been trying to get iTunes to recognize all of the albums I put in its Library. I tried everything I could find online, but to no avail. I could find a part of the songs I was trying to get to show up, but not all of them.

For context, the song I experimented with below is a 27.4MB FLAC file with 1042kbps bit rate. I am using iTunes for windows with the goal of setting up a small library of songs to play on my train ride tomorrow from my iPhone.

What I found was, if I transcoded my 1042kbps file to a 320kbps MP3, it was instantly recognized.

I do not want to transcode half of my songs to MP3, because I set it up so that they get transcoded to 256kbps AAC when going to my phone anyway, and that would be a bad transcode.

What can I do instead, so that iTunes recognizes my songs?

EDIT: no, the thing is literally only the mp3s from my folder get recognized in the iTunes library... more context: more recently I started downloading only lossless stuff, I didn't even know I had mp3s in there

Will I need to make a script to transcode every one of my FLACs to 192 AAC? Can't I make iTunes recognize them and transcode them himself