Vatsim has a recommended routing from Katmandu to Lukla which can be found in this “Lukla Handbook”: https://www.nepalvacc.com/wp-content/uploads/2021/08/LUKLA_HANDBOOK.pdf
The recommended routing via GPS is VNKT-KTM-VNRC-VNLD-VNLK
Unfortunately the airports VNRC and VNLD can’t be found in Simbrief, and VNLD can’t be found in Navigraph.
I’m linking to Wikipedia so you can see which airports this is: Ramechhap Airport - Wikipedia
Lamidanda Airport - Wikipedia
Would be great if your data can be updated with those airports so they can be used as waypoints in Navigraph.