The video in the English translated link did not work for me. It did work in the original German link.The article has a very interesting video in English showing the inner works of these printers.
How does the printer maintain strict control on the refilling process, ie not let us refill with third party inks?
I think Canon India's explanation could suggest that something similar to the yellow CLI-42Y ink for Canon Pro 100 is used. This ink can cause gelling if it is mixed with aftermarket ink or even water.I have not seen any specific tricks to prevent refill with third party inks. But when you read the small print in the technical specs at the Canon India site you'll read that warranty is excluded in case such third party ink is used
'Using non-genuine inks may affect the printer's performance and/or the print quality. In some rare occasions, although there are no safety issues, using non-genuine inks has caused overheating of the print head and smoke emission from the print head due to the absence of an ingredient found in genuine ink. ' Quoted from the Canon India site
So usage of such ink is apparently technically possible, at the risk of loosing warranty.