Key Fob Curiosity

[Hawk]

I went to take my car out of storage and my key Fob was not working so I could not unlock the door(the battery was dead in the fob) So I used the key to open the hatch back to connect the batter charger while I went to get a new fob battery. After I opened it I noticed I had the key from my 2018 Challenger. I checked the keys and found out the key from the challenger will open the trunk of the viper but the viper key would not work on the challenger. Is the keys on the viper a universal key ? Has anyone experienced this or do I have lottery luck?
Dennis