Thanks for the update Desmond, I"m glad to hear your 9880 is now set up and working well with Piezography inks.
Regarding your 4880: if you replaced chips on the carts, and the chips were not attached flat/flush on the carts, then yes- that could have caused damage to the printer's chip sensors. This would show up as a consistent "NO cartridge" error for the position with the damaged sensor, no matter what cartridge you install.
It is NOT possible that Piezography inks damaged your print head. We have thousands of customers using Piezography inks in a wide range of Epson printer models for many years, with excellent results. Piezography inks are totally compatible with Epson inks, as is PiezoFlush.
If you didn't open the air vent plugs when installing the Piezography cartridges in your 4880, and attempted to charge your printer, this would have certainly caused no ink to print from any channel due to a vacuum being created in the ink system. The 4880 cartridges have air vents, which MUST be open for proper ink flow when the printer is in use- though, we recommend closing the vent holes when the printer is not in use to prevent evaporation and contamination from stuff from getting inside the carts. It could be possible that the print head or pump experienced strain if the cartridge air vent holes were not open prior to charging your printer with Piezography inks, though often times (a few other customers have accidentally forgot to open the vent holes over the years), this is resolved by opening the cartridge vent holes and preforming another Initial Fill cycle.
Please let me know if you have further questions, or there's anything else we can help you with.
Best regards~ Dana