Fern leaf texture missing, can't do anything to get rid of the pink texture of death

Hey!

So I am kind of new to blender therefore there must be something that I am doing wrong regarding this following issue... at 1:32:00 when switching to texture painting in solid view, my object appears pink. I know that pink means that the texture is missing. However, the texture is saved in the corresponding folder (texture which was just created - a simple green color to which i was supposed to add a gradient overlay). Initially, in material preview everything looks fine, not pink like in solid view. However, upon me desperately trying to fix the file, it turned to pink in material preview as well.

So texture is saved where it was before, I did not move any files from one folder to another, I tried File>Report & Find Missing Files and nothing changed. I tried deleting all of the assigned colors (materials and textures) from the properties panel and still nothing changed. 

While trying to work this issue my Blender 2.92.0 app kept crashing, shutting down while I was only in the properties panel. Also, I am on a 2020 iMac i7 and as the blender file contains only a few simple leafs I doubt that it may be from the pc. 

Please help a silly newbie out, I'd highly appreciate it and thank you in advance for your time!

Here's a link to my blender files if you wanna take a look: https://we.tl/t-EcPRmi45u9

library>props>fern>fern.blend -  for file

Screenshot 1: Normal looking colors (previously used on palm tree), newly added green color in the left uv editor - in material preview

Screenshot 2: Switching to solid view and then texture painting pink texture of death appears

Screenshot 3: I don't know what the heck I've done while desperately trying to correct my project but now it seems that they all turned pink, i'm sorry dear fern what have i done to you