All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Such person does not care about committing sins in order to increase his sales. Therefore, a Muslim who fears Allaah and hopes for His Mercy should not enter in partnership with this person.
In case one enters with him in partnership, he will endorse the forbidden things which the person is doing like those you mentioned in the question. For instance, fashion shows are forbidden because the women who advertise the product are scantily dressed and men see them; there is no doubt that this is forbidden. In addition to this, agreeing with a movie star to advertise for his product leads to a great disadvantage which is supporting such people (actors) who are causing corruption on the land.
In case one does not endorse what the other person is doing, he will enter into disputes with him, which will eventually lead to the dissolution of the partnership.
Furthermore, such a partner would not bother whether he earns his money from Riba (i.e. interest or usury) means or other illegal earnings, and this is something a Muslim should avoid.
Therefore, one should avoid entering in partnership with this person in principle.
Allaah Knows best.