@vfarrand , I have the exact issue, or should I say I had the issue and am working through it.
What helped shed light on the solution for me was this post: https://www.jamf.com/jamf-nation/discussions/26918/recon-an-unknown-error-occurred
As the post states, there is a problem with the latest round of Apple updates, having more than 31 characters in the name and the Jamf Pro server chokes. That causes recon to fail and inventory isn't being submitted up.
I didn't perform the recommended editing of the XML file called out in the article. I'm waiting for Jamf to issue a fix.
I did uncheck the box as the article recommends and have been watching a group of folks who have not submitted inventory in >4 days dwindle down in number. It was as high as ~150 but now is at 39.
Hope that helps.
