All the compounds mentioned are organic compounds with sulfur in them. Nothing wrong with that, but it’s odd they’re all organosulfur species, as on Earth the vast majority of smaller organics produced by living critters do not contain sulfur. Some certainly do, but it’s curious everything they’ve picked up on Mars does contain sulfur.
Not sure if they looked for brimstone.
That’s very bigoted of you to say that all martians were denziens of hell!
/s