This is an odd case. Looking at galaxyproject, it seems like a singularity container for poseidon-trident:1.6.7.1 exists, but it is not listed in the Biocontainers registry.
I was told on bioconda Gitter that https://biocontainers.pro is outdated. Is that maybe the source of the issue?
Biocontainers index for poseidon-trident: https://biocontainers.pro/tools/poseidon-trident
Galaxyproject link for poseidon-trident: https://depot.galaxyproject.org/software/poseidon-trident/