Giggling Butt was said to have told her mother-in-law: "Don't worry, he won't die." Amjad, 36, survived the flames - but died 13 days later. A relative said of the attack last month: "It was horrific. The flames were reaching up to 20ft in the air. People who had been at a nearby wedding tried to douse them.
Amjad's father Nazeer said that Butt had fought with Amjad before the attack, throwing a mobile at him. He also claimed that, while his son was in hospital, Butt had tried to poison him with acid disguised as "holy water from Mecca".
In a police interview before he died, Amjad said: "There was an argument. She argued with me and she started abusing me in dirty words."
Butt is due in court in Pakistan charged with murder next week. She could face life in jail if found guilty of the attack in Roli, Kashmir.
The couple met there while she was a government health visitor.
Butt moved to Luton, Beds, after getting UK residency shortly after they married.
She stayed for nine years, working at a Burger King, but moved back to Kashmir in June.