Using the average number from that source you get 356,000 PKR yearly * 30 people = ~$64,000, even using the low end from that site is only a factor of 2 off not 10. The numbers were actually based of the high end from above in the chain "for one laborer to clean panels is probably about $250-300 a month (USD equivalent, in rupees) in that area. That would be a good wage compared to construction work or farm work in that region." which corresponds very well to the high end from your source of 540,000 pkr.

This comes out to ~$97,000 which is how I came up with about $100,000/y.

Just to note this isn't something you do for just one month per year if that's how you came to a factor of ~10.