It's honestly so basic and elementary. You call the timeouts on defense , you're saving almost 40 seconds because the other team is going to burn as much as they can.
You wait to use them on offense, you're only saying how much time it takes you to rush up to the line and run another play, so about 15-20 seconds. Ergo, Matt Lafleur cost his offense at least 20 seconds with a basic clock management mistake.