"Debunked extensively" is a stretch:
On Nov. 8, Newsweek issued a correction, writing, “This article and headline were updated to remove the reference to the Iranian Parliament voting for death sentences. A majority of the parliament supported a letter to the judiciary calling for
harsh punishments of protesters, which could include the death penalty.”
And
"Marashi noted that there is precedent for mass executions in Iran, which he said could help fuel the claim of widespread death sentences for protesters."
“In 1988 thousands of political prisoners were executed by orders of Ayatollah Khomeini within the span of a few months,” he said. “The rumors of a new round of mass executions is likely fueled by memories of what happened in 1988.
Viola Davis and Justin Trudeau are among the people who shared a viral mistruth about Iranian protesters in the past several days.
www.nbcnews.com
This, on top of the fact that 15000 people HAVE been arrested, it's not a stretch to assume the Iranian government will execute them. They may not now, because everyone's watching.