repossession is an act of last resort to lenders and there would have been a lot of letters, phone calls and maybe even a debt advisor sent round to find a solution. all of these letters, arrears and legal costs will be added to the debt.
Further to this, there will have been a notice of a court hearing to decide a possession order, upon granting the order it is first suspended by 28 days, more letters are sent, a new hearing occurs to grant the full order and a further 28 days would pass by before an eviction date was set, usually.
I do not believe he has paid anything and if he has, make him hand over the payment slips and go to the bank with him to make sure he makes a complaint - I seriously doubt he will do this, because he is lying,
This is serious and the first lender (mortgage) has no choice but to go along with this.
My advice is to go to the court, apply for a hearing to have the order set aside or suspended, this will cost about �60. Your friend should go with her ex, explain truthfully what has occured and make a committed (and realistic) promise of payments. Your friend is jointly liable and must contribute / take control, or the possession will occur. Courts will always favour with the owners, if they can see that the promises made are sincere and realistic.
When this is done, reduce the price of the house to make it quick sale, but be sure to be 100% clear that the settlement figures for the mortgage and secured loan do not exceed the net value achieved in the sale. If it does, extra will need to be paid by your friend or her ex to settle the matter, or the lenders can refuse to allow the sale to complete.
A lender can chase one, other or both names on the loan, so tel lher to act fast, this can be turned around.
Good luck