Filing has closed for the May 2020 Nebraska primaries. Mark Elsworth, somewhat to his surprise, is the default Democratic Party nominee for U.S. House, 3rd district. No other person filed in the Democratic primary for that seat. So it seems inevitable that he will be the Democratic nominee, even though Nebraska does permit write-ins in primaries.
The Third District is the most rural part of Nebraska, including the western two-thirds of the state.
As a result, Elsworth will not be the presidential nominee of the Legal Marijuana Now Party. Instead the party presidential nominee will be Rudy Reyes.
I believe this happened a week and a half ago. At least according to a facebook post by him at 6:01 pm on March 2: https://www.facebook.com/markjr4gov/