The lack of a video is easy to understand.
The musicians go into their home studio and do a few passes and send the tracks to Guy. Guy takes them and edits them into the song, probably "comping" a few takes.
To ask the musicians to do a video is a whole different prospect. You either have to ask them to film the original time recording, or you have to ask them to be filmed miming to the finished product. Either way, you are talking about 60 x camera persons/lighting/make up whatever. Yes it's possible but it's not really practical, particularly in an age where basically very few people "pay" for music and the object of the exercise is to raise money for charity.
It's easy to fix though. And hope it's something we'll see in the finished video (which wasn't done in 2+ years for some reason, and considering expectations are meant to be broken, I doubt that). All you need to do is yes, ask people to record themselves playing, on their phone, laptop, GoPro, security camera or whatever. They all have guitar techs, wives, producers, and mates who can help them, even fridges have cameras these days, so it doesn't need to be good.
A shitty video of a celebrity worth more than any 8K RED camera footage a fan can record.
Obviously, not everybody will do that, then you can just cut to "house band" playing or Mark playing, displaying the name in the video somewhere.
Hard to edit? Well, maybe, but you have names of guitar players in audio tracks, and you can even synchronise the audio automatically, no manual labour is needed. With original videos and a finished audio track, I could complete this task in a few hours. All this tells me it wasn't in the pipeline. And if it wasn't in the pipeline, it's bad production, as simple as that.
