Your shield should be recharged when an enemy quit on your finisher!

@bosourd Your shield still recharges if enemy quits while you are doing a finisher. In fact if he quits while you're in a finisher he actually helps you because it ends you finisher faster and gives you the shield faster. What you are experiencing is a squad wipe. If you start finishing a downed opponent and your squad or another squad kills the teammates of that downed opponent you won't get your shield recharged.