1997 A4 B5 2.8L 12v V6

Hi - Background.. I have had the battery checked and have been told it is good. Alternator and Starter are good too.
So the issue is this. If I do not drive the car for several days (at least 4 maybe three) the car will not start. There is some juice left but it is not enough to start it. Just enough to start to turn then it will just not turn at all (cannot start).

This is what I have done- I have charged the battery to about 12.5-12.6 volts and then checked for a draw by disconnecting the Negative Cable and touching the cable with the positive lead and the battery terminal with the negative lead. I am getting a draw of 23-28 milliamps. From what I understand that is not enough to cause this. So I am baffled. This is new to me (Electrical repair) so I definitely could use some direction and help.

Could the starter be causing this yet not register in the Meter? Thanks for he assistance.

Also what is the smaller lead from the positive battery cable going to. The one that is attached to the cable itself just behind the cable connection?