Substitution of Trustee or Assignment of Deed of Trust?

[Manuel Sarabia]

I purchased a junior lien at auction. The owner that foreclosed on it actually wants to buy it(They are current on their first, they love the house, and actually want to purchase the title from me). Would a substitution of trustee be the form to use, or an Assignment of Deed of Trust? One escrow office said Substitution of Deed and another said Assignment of trust. But both couldn't offer an escrow service. Still looking for an escrow company that can act as a third party and will eventually contact attorneys for it, but would still prefer an escrow company.