debts

As Legal heir whether it is Wife or Son or Daughter, it is your duty to pay the dues of your deceased Father.  However, you liability is limited to the extent of the assets inherited (both immovable and movable like cash, jewellery or bank deposits including SB account).  In your case, since Father's terminal benefits are credited to the account of your Mother, the Creditor can proceed against your Mother to pay the amount of dues to them towards your Father's debt.

Please understand the subtle difference.  PF, Gratuity, a pension when with an employer cannot be attached. But, when they are in deposited in the account,  they are no more such TB but take the shape of bank deposits.

Those who filed suit can not remain silent after obtaining decree and may be soon filing Execution petitions, and you may have to defend it.  So immediately contact advocate who can offer suitable advice.  Normally he will advise you to withdraw all the balance immediately before the amount is attached.

In my considered opinion, the funds, , such as gratuity etc, which the mother  has received in her capacity as the wife of the deceased employee cannot be considered as estate she has inherited from her late husband. As such, such funds cannot be attached in execution proceedings.