You have to bear in mind that these guys are not paranormal investigators, just urban explorers. They have a Youtube channel that they report their explorations on regularly and apart from some spooky happenings at some of the sites, they do not generally report on the paranormal.
This is actually an oldish video (it was actually released in August 2020) that has already been seen on British TV (although for the life of me, I can't remember which show, although I want to say 'Paranormal: Caught on Camera'), so not sure why this is just turning up now in the papers and on Youtube. There was a whole debate about whether it was a homeless person, but as the gents clearly state (and can be seen in the video), the figure moves off to the right of the stairway bannister where there is actually nowhere to go, apart from down the stairs, as it is a brick wall with a very small boarded window in it.
Having analysed this video after it first came out, what is really interesting is that you can clearly see the figure come into frame from the fire exit door, moves back to the left and it almost seems like it notices them before moveing back to the right. You can also hear movement above them. What is also interesting, is that there is enough light from their equipment to illuminate the plinths on the bannister and to slightly illuminate the fire door behind, which you can clearly make out in the analysis. The figure has no light reflection at all and is just a dark mass.
Other things to note, is the point of light that shows for a second around the 'foot' area of the figure. This could be light reflecting off the metal kick-board on the bottom of the fire door, or the radiator bracket on the wall, but it seems to move with the shadow figure momentarily before disappearing. Also, the black figure actually casts a momentary shadow on the back wall near the fire door as it moves from center to the right of frame. It is very subtle, but it is there.
For the skeptics out there, and to put another side on this, what I do not like about the video is that after they catch the figure, the camera pans away and down before going up again. This could have given enough time for someone in the building (although, goodness knows who would want to be in an old care home in the dark!) to move back through the fire door and into the corridor or rooms that it leads to. However, they do actually follow up in the other areas and they found nobody in the building.
In the end, the guys do seem genuinely spooked by something they saw and heard. Was it paranormal? I do not think there is enough evidence here to determine either way and it would be nice to see this site investigated by a team.
This is the full video from their visit.