3 loans on a property like that is not uncommon. SD Realtor is right, check the title report first to see if the new owner really was the 3rd junior lien.
Nevertheless, I would not offer more. I’d wait a couple of weeks and offer less. Then if they counter just thank them for a good time and walk away. Then come back a couple of weeks later with an even lower offer.
A properly done short sale would have wiped out the 2nd and 3rd and given you $.cents on the dollar off the 1st.