Dr. Cooke,we speculate they can here:
Sykes, A.V., Almansa, E., Ponte, G., Cooke, G. and Andrews, P., 2020. Can cephalopods vomit? Hypothesis based on a review of circumstantial evidence and preliminary experimental observations. Frontiers in Physiology, 11, p.765.
As a very recent convert to cephalophilia, I think I can safely say that I am alone in my extensive circle of friends and acquaintances who find this subject fascinating. I wonder, however, (a bit off-topic) how one could go about collecting and analyzing cephalopod fecal matter, as I suspect it would be immediately diluted and dissipated in the aquatic environment. I’m thinking primarily of the degree of ingestion of plastics to be found in wild octopuses.