Proper way to write out User Attributes (Manual definition mode) in AutoCAD Writer so that they are visible in ArcGIS and AutoCAD?

I am writing out AutoCAD points--no blocks--to a new CAD file, but I want to save the Block Name, Layer Description, and Source File info for use later. For that purpose, I have created three User Attributes (in Manual definition mode) in the User Attributes tab of the CAD Writer: BlockNm, LyrDesc, and OrigSrcFile, respectively, and populated them with values from existing attributes. When I look at the attributes of the output CAD file in ArcGIS (Pro or Desktop) or in AutoCAD Map 3D, I do not see these added user attributes. During translation, I get a warning message that the OrigSrcFile value had to be truncated (I'll handle that later), so it appears that the Writer is actually writing out those user attributes. I just can't see them in ArcGIS or AutoCAD. Should I be writing out the User Attribute differently to make them accessible in ArcGIS and AutoCAD? (I do see in help files that ArcGIS Pro reads user-defined block and Civil 3D attributes, but the help does not explicitly mention user-defined non-block attributes. That may be a problem. I just don't know.)