This is basically what I did.
I used a whirlygig tutorial with charm packs. I believe it was off turtle hill quilters blog. Instead of trimming one side to 4.5 I accidentally left it a whole charm square. I still cut everything else the same but it wouldn't line up to a whirlygig so I made the parallelogram instead. When I joined the two blocks together to make it I just trimmed the length down to 8 or 8.5 inches. And then wala my whoopsie was made lol.
I have some spare charms laying around and extra grey already cut for that block so I'll try and sit tomorrow to write it out exactly how I messed it up.
Thanks for the compliments though. It's by far my favorite mistake lol