Got some new Games, idk if those are the real deal or fake ;)

so one copy of my mario kart super circuit shows yellow sunset instead of the blue sunset like my other copy, why is it?

So basically, I’ve had this game for over a decade pretty sure I got it when it came out in like 2006. I don’t remember playing it, but I do remember finding it a couple years later as a kid and it not working then. I’ve now found it again in my adulthood and I took this along with some other games to a local video game store. The worker put 70% alcohol on a cotton swab wiped it and surprisingly got it to the loading screen and I was ecstatic! The worker told me that the 90% alcohol that I used to swab it before probably didn’t work because I either didn’t do it thoroughly enough or because of the high concentration although it cleaned it there was residue left from how fast the solution dries at that level? Regardless I came home put it in my game boy it’s not reading it anymore. (As shown on the pictures it doesn’t read like there’s anything in there and then when I tried again it had those little lines under the logo?) Took a flashlight over it just to check and as shown there are about four pins as you can see in the picture that are almost like a rose gold. I’m not sure if this is oxidation or rust. Does anyone have any thoughts on what it could be or suggestions on what I could try? Should I go to the store and buy 70% alcohol? Why did it work in store but not now like 3 hours later? I fear I know nothing about nothing so sorry if I’m missing something obvious. Also, all my other games read perfectly fine. Thank yall!

I noticed these black dots behind this gba I just bought but after comparing it to my other one I realized the screen is leveraged up off the gameboy about a fingernail worth while my my other gba is flat against the system. Did they make screen protectors for these back in the day where I could just take this off or is it a different model. It came with a bunch of extra stuff so I wouldn’t be surprised if it was jazzed up