I don't enjoy being the bearer of bad news, but it's possible that your cart (or part of the ROM data) died.
I can't say for sure that PKSM messed up your save. If the issue was only a save being corrupt, you should be able to reset the save via loading the game.
However, it appears that even vanilla devices have issues loading the cart (based on the picture you showed us). This suggests the cart, or the ROM data, is dead/impacted to some extent..
Hard to determine who that culprit is, but there's a chance that PKSM was innocent and was trying to load your save while your cart/data died.
At the very least, it appears the ROM header is fine, since the logo shows up on the 3DS, so that is good news.
Tho, it remains that a vanilla 3DS cannot even boot your cart.
At this stage, I don't know what you can do. Try scouring the net for similar issues, and see if they got it resolved.
(Also, if your cart cannot be loaded properly on a vanilla 3DS, then I doubt the save [if it even exists] can be extracted by a CFW 3DS)
In the mean time, I'll leave this thread open, in case anyone have any crucial information to chip in.