I don't understand. The games description clearly says "In Five Nights at Freddy's 2, the old and aging animatronics are joined by a new cast of characters". It specificly says that the animatronics from the first game are "old and aging", meaning that the first game must have come before the second game, or the original animatronics would have been brand new. The pizzeria is "New and Improved". The "Improved" part means that there must have been a worse version before it, or there would have been nothing to improve on. How could the second game take place before the first game?
Have you realized that the FNaF 2 animatronics and the withered animatronics are completely different? There was another location before FNaF 2 that had the withereds, that's where the first murders took place.
The minimum wage shown on the first game’s check indicates that it took place in 1993, and it’s made very clear that FNaF 2 took place in 1987. There’s also the fact that Phone Guy died in FNaF 1, while he’s still alive in FNaF 2.