If so, it shouldn't happen for long since the person working 14 hours a day would inform their manager/boss to

1. Readjust estimates/expectations because a team member has stopped contributing (happens all the time if someone gets sick/hospitalized, there should be processes for this)

2. Address the problematic employee to confirm they will contribute, or fire them

If the actual-worker is still overburdened, then it's a management/company problem and the overburdened should be looking around for new employment.

If someone is slacking off then they need to be performance managed or fired. That's management's problem.