creating a list from cross referenced data

We'll see, but I have a very bad feeling that your sample may have been oversimplified... Can one person be assigned more than one letter?

If yes, please post a realistic sample and watch a grown man cry... If no, then one way to do this is:

helper in I2, copied down:
=SUM(B2:H2)

In N2, copied down:
=IFERROR(INDEX($A$2:$A$6,MATCH(0,INDEX(--(COUNTIF($N$2:N2,$A$2:$A$6)=$I$2:$I$6),0),0)),"")

and in O2, copied down:
=IFERROR(INDEX($1:$1,SUMPRODUCT(--(INDEX($B$2:$B$6,MATCH(N3,$A$2:$A$6,0)):INDEX($H$2:$H$6,MATCH(N3,$A$2:$A$6,0))<>"")*COLUMN($B$1:$H$1))),"")

Please try at

J3 drag down

Formula:

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K3 drag down

Formula:

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Kvsrinivasamurthy thanks for wonderful idea.

ARRAY formulas are used

In J2 then copied down.

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In K2 then copied down.

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