Differently coloured PCBs for KOF2002 AES English

My English KOF2002 home cart has differently coloured PCBs (one is green, and the other is light brown). If needed, I will post a photo when I get home.

From your experience, is this indicative of a boot? Or are there home cartridges known to be real, which have differently coloured PCBs?

Thanks in advance

My authentic Metal Slug 3 is the same way. One PCB is white, the other is sorta green like how PCBs usually come. I think your KOF 2002 is legit.

Thanks for the answer.
I was getting worried also because the cartridge label seems to lose grip around the bend.