Hey @Will
Hmm, that does look a bit odd!
I would suggest taking a look here:
C# Create Item in example
Simple C# for adding an item to a board
Connecting C# to monday.com
Perhaps this StackOverflow thread can be helpful:
StackOverflow - JSON.stringify equivalent in C#
I would recommend avoiding escaping manually, where possible. This can be error-prone and an unsustainable solution in the long-run. Using functions that do that work for you can save you a ton of time 
I hope this helps! Thank you so much for your input too, @basdebruin! You’re always really helpful.
-Alex