Not a good picture at all.
However, it needs some context. I would be curious to see how other goaltenders fared in these situations as well. I have a suspicion, not based on anything, that unless you are truly one of the best goalies (Roy, Hasek, etc.) your stats in this situations as a goaltender does go down.
Here's Quick. They're 2 goalies with similar career games played and similar breakdowns for clinching games vs. elimination games, except one has a reputation for being able to get it done.
When Kings can win a series (excluding Game 7):
2012 Canucks Game 4 - 3/30
2012 Canucks Game 5 - 1/27
2012 Blues Game 4 - 1/24
2012 Coyotes Game 4 - 2/21
2012 Coyotes Game 5 - 3/41
2012 Devils Game 4 - 2/23
2012 Devils Game 5 - 2/19
2012 Devils Game 6 - 1/18
2013 Blues Game 6 - 1/22
2013 Sharks Game 6 - 2/26
2014 Hawks Game 5 - 5/45
2014 Hawks Game 6 - 4/25
2014 Rangers Game 4 - 2/19
2014 Rangers Game 5 - 2/30
14 GP: 31/370 = .916
Elimination games (including Game 7):
2010 Canucks Game 6 - 3/21
2011 Sharks Game 5 - 1/52
2011 Sharks Game 6 - 4/35
2013 Sharks Game 7 - 1/26
2013 Kings Game 5 - 4/35
2014 Sharks Game 4 - 3/39
2014 Sharks Game 5 - 0/30
2014 Sharks Game 6 - 1/26
2014 Sharks Game 7 - 1/40
2014 Ducks Game 6 - 1/22
2014 Ducks Game 7 - 2/27
2014 Hawks Game 7 - 4/41
2016 Sharks Game 5 - 5/27
2018 Knights Game 4 - 1/21
14 GP: 31/442 = .930
All other games (57 GP): 133/1691 = .921