I agree Hegelian thought likely had influence on Marx and Rand, as it had on many other thinkers -- both those who developed his ideas further or in different directions, and those who critiqued or rejected his main points. Though a number of Hegel's ideas have since been discarded, many others have continued to this day largely unchanged, such as his dialectic, or have 'aged well' such as his strong opposition to slavery.

It would seem unfair to lay at Hegel's feet the devastation of communist uprisings. That might even be the case for Marx. While we could say that Marxism had devastating impact on the world (much, much less so for any of Rand's ideas), Marx himself thought of communism as a natural evolution out of end stage capitalism, and one of his main tenets was a verse from the Bible. The slaughter and starvation of millions was more due to the political reinterpretations of Marx, rather than what Marx himself envisioned.

The idea of judging ideas based on those who claim adherence to them is also tricky. The Bible has spawned the Inquisition and also Mother Teresa. The cathedral of human thought -- though also wrought with mistakes and wrong turns -- is a great edifice of each generation building upon the ones before it. We cut out or erase certain thinkers or ideas to our own detriment. That's not to say we should accept every idea, some are just plain toxic. But even bad ideas can spawn good ones: critiquing bad ideas can lead us to better ones, and sometimes we just have to learn the hard way.

Marx took the dialectic of Hegel and applied it to his historical materialism (in this way, communism would be the synthesis that would follow from capitalism). Rand's Objectivism also seems to have been influenced by Hegel's dialectic. Both Marx and Rand have their flaws, but also their great contributions -- Marx with his critical method and Rand with her emphasis on individual rights.