Hi Josh. We have run the Enable COGO GP tool on the layer prior to publishing as a Hosted Feature Layer. I've reviewed the HFL's JSON and was not able to locate a COGO-related setting. I'm suspecting that it may have to do with that, which may explain why the Pro Traverse tool will draw the geometry using COGO but not save the values into the attributes.
Thank you for the suggestion to use Parcel Drafter from ArcGIS Solutions. It is one I'm very familiar with and we explored this option, but unfortunately it will not meet all of the user requirements.
I'm open to other thoughts and ideas if you have them. My instinct is telling me this may be a limitation based on the nature of the issue and the content involved. I will plan to verify with the ArcGIS Online Product Team at Esri just to make sure since I wasn't able to find any online documentation related to this topic.
Much appreciated!