Yellowface type 2 grey greywing cock x Greygreen clearflight cinnamon hen

The facts

Sire: yellowface type 2 grey greywing cock
Dame: greygreen clearflight cinnamon hen

Expected offspring

lightgreen cock/yellowface type 2, greywing, cinnamon
lightgreen dominant pied cock/yellowface type 2, greywing, cinnamon
greygreen cock/yellowface type 2, greywing, cinnamon (x2)
greygreen dominant pied cock/yellowface type 2, greywing, cinnamon (x2)
greygreen (DF) cock/yellowface type 2, greywing, cinnamon
greygreen (DF) dominant pied cock/yellowface type 2, greywing, cinnamon
lightgreen hen/yellowface type 2, greywing
lightgreen dominant pied hen/yellowface type 2, greywing
greygreen hen/yellowface type 2, greywing (x2)
greygreen dominant pied hen/yellowface type 2, greywing (x2)
greygreen (DF) hen/yellowface type 2, greywing
greygreen (DF) dominant pied hen/yellowface type 2, greywing

Observed result

greygreen dominant pied cock
greygreen cinnamon hen

Analysis

Unexpectedly one of the two chicks turned out cinnamon.

Cinnamon

Cinnamon is a sex linked factor. This means that you need a cinnamon or split cinnamon cock to get cinnamon offspring. So the cock must be split cinnamon:
Sire: yellowface type 2 grey greywing cock/cinnamon

Conclusion

Sire: yellowface type 2 grey greywing cock/cinnamon
Dame: greygreen clearflight cinnamon hen

Expected offspring

lightgreen cock/yellowface type 2, greywing, cinnamon
lightgreen dominant pied cock/yellowface type 2, greywing, cinnamon
greygreen cock/yellowface type 2, greywing, cinnamon (x2)
greygreen dominant pied cock/yellowface type 2, greywing, cinnamon (x2)
greygreen (DF) cock/yellowface type 2, greywing, cinnamon
greygreen (DF) dominant pied cock/yellowface type 2, greywing, cinnamon
lightgreen hen/yellowface type 2, greywing
lightgreen dominant pied hen/yellowface type 2, greywing
greygreen hen/yellowface type 2, greywing (x2)
greygreen dominant pied hen/yellowface type 2, greywing (x2)
greygreen (DF) hen/yellowface type 2, greywing
greygreen (DF) dominant pied hen/yellowface type 2, greywing
lightgreen cinnamon cock/yellowface type 2, greywing
lightgreen cinnamon dominant pied cock/yellowface type 2, greywing
greygreen cinnamon cock/yellowface type 2, greywing (x2)
greygreen cinnamon dominant pied cock/yellowface type 2, greywing (x2)
greygreen (DF) cinnamon cock/yellowface type 2, greywing
greygreen (DF) cinnamon dominant pied cock/yellowface type 2, greywing
lightgreen cinnamon hen/yellowface type 2, greywing
lightgreen cinnamon dominant pied hen/yellowface type 2, greywing
greygreen cinnamon hen/yellowface type 2, greywing (x2)
greygreen cinnamon dominant pied hen/yellowface type 2, greywing (x2)
greygreen cinnamon (DF) hen/yellowface type 2, greywing
greygreen cinnamon (DF) dominant pied hen/yellowface type 2, greywing

Observed result

greygreen dominant pied cock/yellowface type 2, greywing, cinnamon
greygreen cinnamon hen/yellowface type 2, greywing