Here are some possibilities for your neighbor. I didn't check the
growing zone but they will take the shade and do have good height.
Acanthopanax sieboldiana 'Variegatus'-Acanthopanax
Acer circinatum-Maple, Vine
Actaea racemosa-Black Cohosh
Actaea simplex-Bugbane
Astilbe c. 'Superba'-False Spirea
Astilboides tabularis-Astilboides
Athyrium filix-femina-Lady Fern, Uncrested
Chasmanthium latifolium-Northern Sea Oats
Corylopsis sinensis-Chinese Winter Hazel
Fuchsia magellanica-Fuchsia, Hardy
Mahonia aquifolium-Oregon Grape
Matteuccia struthiopteris 'The King'-Jumbo Ostrich Fern
Polygonatum commutatum-Solomon's Seal, Great