IF YOU HAVE A RESPONSE TO THIS POST, DON'T QUOTE IT. I USE A SHIT-TON OF PICS.
You guys need to remember that he's innocent until proven guilty. To be honest, I was starting to think that he was purposely trading a fake too, until I actually put some time into looking into this shit:
1.) Tag Placement
Collar doesn't come down enough on the M, and the sewing on the tag is all bunched up.
Should be like this:
Not necessarily true. My size M doesn't go down that much; it cuts off right after the "Supreme" tag and blocks off the M. Same goes with whoever runs the YouAintSwift resale site.
In addition to that, if you were to force the shirt to fold along the hem, you'll find that your tag will be much closer to the lower end of the collar.
2.) Repeat Pattern
As @slytendencies said,
"You see how the bunch that has the small pink flower on top is only paired repeatedly with a small peach flower under it and a white flower on both left and right sides, then the other bunch of flowers is a big pink with a black to its right, on his the pattern seems to be completely off...its hard to believe someone could fake this but if i were you i wouldnt do the trade."
If you look closely, both shirts have both patterns you described. Supreme went a little more complicated with the repeating pattern than you might've thought.
a.) The blue triangles represent the "pink-peach-MAROON" rose-repeat pattern.
b.) The red triangles represent the "pink-peach-WHITE" rose-repeat pattern.
The pink & peach roses are used twice in different patterns, one next to the maroon rose (bottom right of blue triangle), another next to a white rose (bottom right of red triangle).
c.) The green squares show that each shirt shows the exact same print. You can see, by using the green squares as references, that the pattern is similar all around the squares as well. The pattern doesn't fit exactly, due to the orientation of the picture.
I feel that the only major contrast between the two is that your black threading happened to fall on the light-colored part of the print, whereas his happened to fall on the dark-colored part of the print. Aside from that, it's a pretty standard stitching, I don't really see anything wrong with it.
4.) Mini Logo
This is the only part throwing me off. Everything seems on point except for the fact that his "S" is thicker. Could be from random variation. My PCL tee matches with the thinner "S", if that helps.
Small-stitched letterings usually follow distinct "pixelated" patterns, similarly too how you can see how many pixels make up a letter when you zoom in on fonts on your computer. You should be able to tell by eyeing it closely whether the stitching matches perfectly or not (I can't really tell from the pictures alone).
I'm not saying that this definitely is or isn't fake. I'm just providing some additional things you might have overlooked. I mean, to be honest, you pointed out so many flaws, that you should return this regardless of whether this is real or not.
On a personal note, I appreciate that you initially didn't want to expose the trader until you were completely sure that his shirt was fake.