https://en.wiktionary.org/wiki/viral
“Viral” isn’t actually used to describe anyone or anything in the article itself, which betrays editorial idiocy and/or carefully calibrated clickbait, rather than actual changing definitions.
The linked article is about two of them.
> Does anyone really know what “viral” means?
Several people, at least, are familiar with all the forms you've linked .. including (4)
(advertising and marketing) Spread by word of mouth with minimal intervention, in order to create buzz and interest.
If it's any consolation, it changes faster than even descriptive dictionaries keep up - it must be purgatory for the prescriptive gate keeping ones.
Don't blow a seal, it'll be a mess for others to clean up.