Arsal Khan Khichi is believed to be in Dubai, the BBC reported. His cousin, the victor in an election in Punjab, did not partake of the poisoned meal in Mailsi.
Vehari Sadiq Ali Dogar, a district police officer, told the BBC's Urdu service that Mohammed Rafiq, who cooked the meal, admitted the poisoning.
Rafiq allegedly told investigators Arsal Khichi paid him 100,000 rupees ($1,000) for the poisoning.
Investigators said 50 people were sickened by the meal and 22 died.
"If Arsal Khichi claims he is not involved in this case, he must come back, face the court and prove himself innocent," Jehanzaeb Khan Khichi, the cousin, told the BBC.