The fares to Nepal are very expensive this year. If you are able to travel for 4 months, you can travel out from the US between Sep 5-15, and return after Jan 15, 2023, fares will be far cheaper. Or travel out of the US after Jan 15 and return by April/May and you'll see prices decreasing.
It does not matter which website you review, prices are more or less the same.
This year the fares are expensive because only a limited number of airlines operate between US & Nepal. Additionally, Qatar has reduced the number of flights to Kathmandu during the World Cup in Nov & Dec. Fares are expensive in the fall because of Dashain, Tihar, World Cup, and of course x'Mas travel.
If you want us to look for cheaper prices, contact us Zen Travels (202-552-1508) or check online at zentravels.com