You have to take this into account, when you look at the dynamic range.I think that paper actually tends to support that HLG is superior to V-log L, no? At least in terms of having superior dynamic range.
As I mentioned the devil is in the details, you have to look at the gamma curves, knee, nose, internal camera settings, etc etc.Note that these figures are a little speculative and subjective: it is up to the user to decide whether the performance at the extreme ends of the dynamic range are acceptable, thus there is an uncertainty of about 1 stops in all these results.
Since HLG is designed to be a delivery format, Panasonic is doing more internal processing. For example Panasonic does a lot of NR in body for HLG, so a lot of times the shadows are soft. V-Log is closer to raw, in that you get more to work with in post, including noise. This is why a lot of people over expose V-Log by 1 to 2 stops as a rule of thumb, so that in post the noise in the shadows will be crushed.
The simplest way to think of it, is that V Log (or any of the log formats) is designed to offer more leeway in post, while HDR is designed to be left as is out of the camera.