Null Reference in Line 186 of RemoteLRS.cs only with some LRS endpoints

[bstevens762]

Hi,
I have recently gotten xAPI messages working out of unity to the Scorm cloud LRS. However, whenever I attempt to use the endpoint I actually want to use I get "Object reference not set to an instance of an object" in the Catch block on line 186. Is there anything in particular that could cause this on my end? And if not, is there anything glaringly wrong with their url?

connection succeeds at: https://cloud.scorm.com/tc/(MyUserID)/
WebException caused at: https://me.backpack.education/planner/api/

Thanks for your time