There are multiple hyper-warming scenarios that have been postulated over the years. Look up the clathrate gun, ocean circulation collapse, arctic albedo flip.. some are now considered unlikely.

I don't know if any would be a Venus scenario, probably not. But we don't really need that much warming to kill ourselves off. Average global temps in the Eucene were up to double what they are today, that would do the job :)

And while not all the way to Venus, Earth's history has multiple mass extinction catastrophes that have happened. Some have been due to things like asteroids, or volcanism but also just chemical imbalance. An ice age is small beans compared to those...