VLOOKUP Multiple Occurences of Same Reference?

not overly efficient but on Sheet1:

C2: =$A2&":"&COUNTIF($A$1:$A2,$A2)
copy down

then on Sheet2:

B2: =IF((COLUMN(B2)-COLUMN($A2))>COUNTIF(Sheet1!$A$1:$A$1000,$A2),"",INDEX(Sheet1!$B$1:$B$1000,MATCH($A2&":"&COLUMN(B2)-COLUMN($A2),Sheet1!$C$1:$C$1000,0),1))

Apply the above across your comments matrix... I would personally insert a column onto Sheet2 to hold result of COUNTIF (or place in a column way off to the right) such that you don't need to call it in each cell in the comments matrix (hideously inefficient) -- you can simply reference the cell holding the result of the COUNTIF... eg assume

Z2: =COUNTIF(Sheet1!$A$1:$A$1000,$A2)

Then:

B2: =IF((COLUMN(B2)-COLUMN($A2))>$Z2,"",INDEX(Sheet1!$B$1:$B$1000,MATCH($A2&":"&COLUMN(B2)-COLUMN($A2),Sheet1!$C$1:$C$1000,0),1))
Apply across range as before.

Note the above are based on your sample file layout.