Well, mutations in the morpholino binding site should suppress the phenotype - and they do! The origins of this paper go back to the 2018 Zebrafish Meeting in Madison, WI, where Carlee and I were discussing the challenges of ascertaining morphant phenotypes and decided to give this particular solution a try. Short 2.5 years later (no irony here!), the paper is out. I hope you find it interesting and useful: https://www.nature.com/articles/s41598-020-71708-1
Darius
Darius