What you were saying is not correct. This is not a town. A town is defined by OSM as “ An important urban centre, between a village and a city in size.” There is no village or town called kartarpur - it is a gurdwara complex, that’s all. It is not a town on local maps either. There is a Wikipedia article that incorrectly calls it a town which is wheee the confusion may come from, but you can use satellite imagery and see clearly that the gurdwara is not a town. It is fact near villages that have a totally different name.

It is not listed as a town on the Narowal district website https://narowal.punjab.gov.pk/. What *official* map are you looking at?

2) “Kartapur Corridor” does *not* connect two major towns. It connects a gurdwara with a pilgrim reception centre on the Indian side. That’s all. No one is allowed to travel from India to Narowal, or Narowal to anyplace in India using this road. That is why it is not a highway. It only connects a temple with a reception centre, and only special carts can use this road. No other traffic is allowed whatsoever.

GT road east of Lahore is arguably no longer functions as a trunk road as it does not functionally connects Amritsar and Lahore anymore. Indian cars cannot enter Pakistan and vice versa. Until 2019 only
Trucks could cross at the integrated border post. Only foot traffic can now cross the border. 

The maps incorrectly depict roads and crossing which do not exist. The only road connecting both Punjabs is at Wagah. Nowhere else. That is why there are no other cross border highways. We have to depict reality.