Surely this places an upper bound on photon length or its statistical distribution?
Basically, the latter. Photons don't have a "size", because of the issues identified in the answer you've linked to.
What you're seeing in the video is a wavepacket, i.e., a confined light wave moving in space; this consists of a large number of photons in the video shown but it is perfectly possible to have a wavepacket that contains a single photon. The length of this wavepacket is inversely proportional to the bandwidth of the wavepacket, i.e., the length of the interval of wavelengths that combine to make up the wavepacket.
In principle, it is possible to make wavepackets that are as short as you want, so long as you have a light source with enough bandwidth to sustain them. For light sources in the infrared, the titanium-sapphire laser used by Raskar has basically been taken to its bandwidth-limited form, as showcased here and in related questions. Shorter pulses have been achieved (though not with laser light - you need to start with a laser and then generate high-order harmonics from it) with bandwidth going in to the ultraviolet and extreme UV regimes. Raskar's camera is probably unable to resolve those, but it's conceivable that a modified version could keep up.
If you want to look those things up, though, the key metric to consider is to look for the temporal duration of the pulse as it passes a fixed location (so, femtosecond pulses for IR lasers, and attosecond pulses for the ones generated by their harmonics), and this will give you much richer search results. Since light moves at a constant speed, the two quantities are directly equivalent.
But, again, this is all a property of the classical wavepacket which contains the photon - it does not tell you anything at all about the "size" of the photon itself.