Why is textureit not working? It's working fine for me and just does not include the latest textures of the game.
You can easily use and search for "play" in there.
Other possibilities are searhc offline with Black Book Browser in the game's *.mnf files. You can search for .dds files there too.
Or check UESP texture archive for the correct files, they are provided as .png files. If you extract them to your disk you can use windows search to find the files by their name, and the folders are the same as they are ingame so you are able to build the path for yourself that way e.g. /esoui/buttons/...dds
Some textures are also mentioned here:
https://wiki.esoui.com/Textures
And a list is here (but it most probably is outdated and even older as textureit list):
But this link also includes the info about textureIt, Black Book Browser, ESOExtract Data and the UESP *.png files!
https://wiki.esoui.com/Texture_List