Digging around for some fares out of Asia we found a couple of nuggets which I hope will benefit someone here, even if this routing is slightly esoteric.
If you can get yourself over to Kathmandu, you can fly Etihad's business class from all the way to Paris with the obvious transfer in Abu Dhabi, for €1364, £1169, $1500. This is before applying a further discount if you are an American Express cardholder.
For only 30-40EUR more, and if you are a die-hard Formula 1 fan, some dates we tried also coincide with the Abu Dhabi Grand Prix which might make for an interesting and spectacular stopover.
Dates you can travel
You can basically travel immediately, but that should allow you enough time to get to Nepal. Fares are wide open nearly every day until end of September 2020. There is a maximum of 8 months stay and no minimum. You can stop over in Abu Dhabi free of charge (and get in on the Formula 1 action as described above!)