The current trend of late stoppages in Japan -- particularly with older fighters like Yoshida and Sakuraba -- leads me to believe a serious injury or death in the ring may be most significant blow to an eventual demise of PRIDE as we know it.
Although there's already heavy scrunity on DSE for Yakuza ties, etc, fighter safety is being stressed less and less. Unless there's suddenly voice for more restraint, fights will continue to end late, and momementum of casual acceptance will continue build, setting up what could be a huge crash.
The fighter most likely will be very popular, or even an icon, so fans will be overwhelmed. Though Japanese media is not my expertise, I have to imagine in due time some outlets will heavily criticize DSE. Public scrutiny will in turn grow, and, eventually, formal action will be taken by the government.
Once new standards (likely similiar to what NSAC/UFC now accept) are in order, though, it will be too late. Casual and potential fans in Japan and elsewhere will be turned off, any new TV deals will fizzle, and the organization will go bankrupt.