Thanks to Jordon for the following.
I'm not sure if you count IMDb as a good source for episode titles, but whenever they have had a title of Grimm before anyone else they have been correct, so if you count it as a good source then here are links to episode 404 and 405 of Grimm's titles
Episode 4.04 - "Dyin' on a Prayer"
http://www.imdb.com/title/tt3882292/
Episode 4.05 - "Cry Luison"
http://www.imdb.com/title/tt3955452/
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