If Kamo is enabled, Origin will not connect despite having all relevant sites excluded in Kamo.
It also prevents logins to ea.com and origin.com.
I'd consider this a bug, but either way it needs fixing.
What would be VERY USEFUL is a 'Disable Kamo' button within Kamo, rather than having to completely close it.
Thanks for reporting this; I've not been able to reproduce the issue (I was able to open Origin and even run Sims 4, even with Private Connection turned on. Sims did experience a crash in that specific state, but that might have more to do with how I've crowbarred its save data into OneDrive than anything else. :) ), but I'll be happy to get this to our development team to investigate further.
May I ask if this occurred only when the Private Connection feature was enabled, or even when it was turned off?
As for a 'disable Kamo' button, I might propose that closing it entirely would be the better option - that way, since Kamo isn't running at all, it cannot possibly be interfering with that task you're trying to perform. I'll still mention your suggestion, though, of course.