This is the 11373rd most frequent Russian word.
дизайнера
Designer.
'дизайнера' is the direct object (accusative case singular masculine form) of the verb 'наняли'.
Мы наняли дизайнера для оформления офиса.
We hired a designer for the office design.
'дизайнера' is in the genitive case to indicate possession (work of the designer).
Работа дизайнера действительно впечатляет.
The work of the designer is truly impressive.
Incorrect use: 'дизайнера' should change to 'дизайнеру' to properly match the dative case with 'благодарен' because gratitude involves indirect object to whom the thanks are addressed.