Finally found the full text in the Manos Halevi its on passuk 5:13 (text of document is on next page):
My translation : "I am Haman the son of hemdasa from the linage of
agag,I was sent by the king Achashverosh to fight a war against the
city of Hindahka,the king placed me in charge of 60000 soldiers,and he
gave me food to support them,and he did the same for Mordichai the son
of Shmi (the son of Kish) from shevet Binyamin,I wasted all the
belongings of the king,and I did not have enough money to support the
troops of the king,I went to borrow from Mordichai with interest,And
he said to me it is not permitted to lend me with interest since esav
and Yaakov were brothers,I was unable to do anything until I sold
myself to him as a servant,and if I stopped being his servant,or even
I don't admit to being his servant,or I don't show up for my work as a
servant for one day of the week all the days of my life and my son and
my sons son until the end of days,or have hatred because of the the
sale of selling myself to him,like esav had towards Yaakov because of
the selling of the bechorah,then you should uproot a piece of wood
from my house and hang me upon it,I accept on myself, Haman the son of
hemdasah from the seed of agag to be the servant of Mordichai the Jew
like all that i have written in this letter,With my own will, and my
wanting."
(If I made a mistake please correct )
