I don’t have experience using refrigerant for cannabis extraction, but I have worked in a plant that used it to remove mineral oil from polymer based fiber post spin. We ran through activated carbon beds to strip out the bulk oil and then went into distillation for final purification of the solvent. The only chemical we ever ran into issues with was a deliberate introduction of bleach. The bleach transferred through the distillation process and carried over into the solvent preheaters where it underwent a chemical reaction and became extremely corrosive (most likely chloride stress corrosion cracking) to our stainless piping. We first noticed the problem when we began developing pinhole leaks at stainless weld joints, and in the end replaced hundreds of thousands of dollars of piping and condenser end bells.
Like I said, not a chemist, so I’m not sure if any of that info was helpful, but I hope it was at least interesting.