|The following is based on Fallout Tactics and some details might contradict canon.|
If only First Scientist Napstarsky or Second Scientist Jones had survived instead of me. They might have been able to repair the electro-organic linking terminal, and who knows, they even might have saved Vault 0.”— Lewis,Cheyenne Mountain terminal entries - Terminal Alpha
Second Scientist Jones and Second Scientist Napstarsky had died shortly after the awakening of the Calculator before they could repair the electro-organic linking terminal. Third Scientist Lewis tried to do it instead of them but apparently failed.
Jones is only mentioned in Fallout Tactics.