Are the heirs entitled to re-file a lawsuit regarding the partnership in the house after the death of one of the partners and the other partner's denial of its existence, and are the relatives who know about the partnership obligated to testify Islamically?

The occupant's denial of his relative's right to the house is an act of betrayal and usurpation. He must repent and return the right, for the Prophet, peace and blessings be upon him, said: "The wealth of a Muslim person is not lawful unless given with his willing consent," and "The hand is responsible for what it takes until it returns it." The partner's silence out of shyness does not forfeit his right, and his heirs may claim it unless his silence was a relinquishment. The testimony of those who know the truth is obligatory and binding if there are no others, for Allah Almighty says: "And do not conceal testimony, for whoever conceals it - his heart is sinful," and the Prophet, peace and blessings be upon him, said: "Help your brother, whether he is an oppressor or oppressed."