What is this Easter egg referring to?
Solution 1:
The Easter Egg the reddit users are referring to is Mr. Apple. Paul Donovan, who claims he was a developer of the game, wrote the following in response to an email
The apple wearing a red origami hat pictured in the credits is Mr Apple. He was an apple that I bought for lunch one day which Matt Johnson (programmer) nicked and kept on his desk. Katie Lea (mapper) made him a paper hat. He lasted about 9 months without rotting due to the magical powers of the hat. Something to do with pyramids I guess..