Apparently that instruction was left out and it was a lot cheaper to print stickers than to reprint manuals! But there's no reason why it couldn't have been added to the online version. ... Anyhow...

The instruction to avoid Pine Oil, Chlorine, Petroleum or Formaldehyde applies to all toilets 'cuz they're corrosive and damaging to rubber--and so are chemical household toilet bowl cleaners (I'm amazed they forgot to include those!)--and especially to the LS/ES 'cuz they can also damage the electrodes. However, muriatic/hydrochloric acid has long been an approved de-scaling chemical in the marine industry, used by yards in sanitation systems and other raw water hoses... As I mentioned above, Raritan's instructions for cleaning the LS called for it till they figured out they can make money selling a product to do it.

So use muriatic/hydrochoric and common sense and everything should be fine.