On the topic of videos posted around the web, plus a lot of the social media comments (particularly Twitter) I think we all need to treat a lot of them, probably the majority of them, as being faked, tampered with, or otherwise misrepresentative. We all (mostly) want to see Ukraine doing well, and highlight anything negative about Russia, and that is influencing the way social media is reacting, I'm sure. There are people that use some social media outlets, like Twitter, that feel more important if their content is viewed more than that of others. That has to create a strong bias to post stuff to get more views, and some of that stuff may not be as it seems.
Obviously there are a few reliable sources around, but one notable feature from early on has been that Ukraine is very adept at managing the information flow from their country and garnering a lot of support from many countries for the way they are being unmercifully attacked by Russia. I give them great credit for that, the contrast with the almost amateurish way that Russia is trying to deceive is stark. However, the winning side in any war wins partly because their propaganda is better than that of their opponent.
One noticeable feature in many recent snippets on Twitter is that the images are either doctored or are not what they are assumed to portray. It's been winter along much of the active front over the past month, yet we are still seeing videos where there are deciduous trees in leaf, for example. Finding accurate sources of gossip from the front lines is not easy, especially as Ukraine seems to have done a pretty good job over the past few months of stopping a lot of the unofficial videos that were being released (remember all the tractors towing armoured vehicle videos, early on, for example).
No idea how we validate anything that appears on Twitter, to be honest, or in the mainstream media. I think we need to assume that we only have a very vague idea of what might really be going on right now, and that's probably a very good thing for Ukraine.