Help required - Excel formula or Macro - Fill column with data based on cells in a table

Hello

Last night I created a thread with a problem that was going to put me into an early grave, but you wonderful people saved me quite easily.

Seeing as the result was so good I need your help with one other small formula

SEE BELOW POST FOR UPDATED EXAMPLE DATA

Solution provided by Kaper to create tables 2 and 3 (minus the red column)
=COUNTIFS(B$2:B$2000,B2,C$2:C$2000,C2)
and copy it down. now auto-filter everything except 1
you will get table 2

and slight modification:
=COUNTIFS(B$2:B2,B2,C$2:C2,C2)
copy down
and show only values with 1 - you will get table 3 (minus the red column)

What I need your help with is to create the additional column on table 3 that I have highlighted in red.

all it needs to do is list the corresponding point number AND duplicate pair if one exists.

The example data should display what I mean.

Let me know if I am not explaining it clearly

Cheers

Sdak