Nope a Tomar king actually found delhi around 700CE. I has been called Dhilli way before any any islamic invasion in india.
Issue is our history book give credit of history delhi to the sultanate ofc because Marxist historians.
People forget one thing here.
Indraprastha, Dhilika(capital of haryana empire) named after a king called dhillu, Dhili, Dilli(Sultanate and Mughal era) and on wards