Keys are constant across the entire game. This means that if the 1st guard in a row on the Customize Inmates and Guards screen has a red key, he will ALWAYS have a red key, no matter what his name is.

Center Perks 2.0, and the transport prisons require no keys to escape

Rattlesnake Springs: https://steamcommunity.com/sharedfiles/filedetails/?id=1395067423

The Zip It Up and Take Out the Trash escapes require keys. Zip It Up requires a red key and Take Out the Trash requires a Cyan Key Card, which i commonly refer to as "CC"

ROW 1: 1st and 2nd Guards have Red Keys

ROW 2: 4th guard has both a Red key and a CC 11th guard has a Red key

KAPOW Camp https://steamcommunity.com/sharedfiles/filedetails/?id=1395067659

The Glide To Victory escape requires a CC.

ROW 2: 1st and 6th guards have CC's

HMP Offshore https://steamcommunity.com/sharedfiles/filedetails/?id=1395067812

All escapes require Red keys

ROW 1: 1st and 3rd guards have Red keys

ROW 2: 6th and 9th guards have Red keys

Fort Tundra WIP

Area 17 https://steamcommunity.com/sharedfiles/filedetails/?id=1395067961

Keys are required for the I'm Only Human and Alien Technology escapes. IOH requires both a red key and a cyan key. Alien Technology requires a RC (red key card)

ROW 1: 1st and 8th guards have Red keys. 4th guard has a RC 2nd and 5th guards have Cyan keys.

ROW 2: 2nd guard has a Cyan key and a RC 3rd and 5th guards have Red keys.

USS Anomaly https://steamcommunity.com/sharedfiles/filedetails/?id=1395068081

The fast Race to Space strat requires a Red key.

The 3rd guard in the first row is the only guard with a red key, however the last riot guard also has a Red key.