thank you for the help. i truly appreciate it.

It's complicated, because it seems that somehow the direct export from AI was able to be opened up with curves just fine, by Vendor A a couple weeks ago before i used AutoCAD. 

This here attached is what Vendor A sent to me as a screenshot from their own AutoCAD system. This is a different file that I'm editing at the same time, but the same methods are used. The curves look to have translated as fully resolute, although they have of course some basic render quality for display purposes. 

They do not at all appear to be splined.

The issue they had contacted me about was scaling, a separate thing.

For what it's worth to the community here, i'm not looking to just solve this and use AutoCAD for transfers only. I am looking to develop a few 3D designs soon too. I'll be doing that completely within AutoCAD. But in general, i will need to remain capable of doing various imports and exports of DXF files. Different vendors use varying systems, including AI sometimes, and so i need to stay in tune with DXF format translations. So i'm very much hoping to simply understand how to maintain a good DXF file within the AutoCAD domain and a few major vector industry counterparts like AI, etc.