He said it was similar to Growlithe and Vulpix, so that tells me it is furry. I don't think it is a skitty.
Tip of its tail is red and swaying.
It's adorable!
White fur on the top of its head and around the neck.
Eyes are round and yellow.
Going by that, he is likely near Snowpoint City area. This pokemon is likely Ice and 'mysterious' could be ghost, dark or Psychic. It definitely isn't a ghost type, because it wouldn't make that much noise when walking.
Going by the audio, there is something small moving toward the camera. And then there is a bigger, heavier pokemon moving toward it. Also going by the sound, the first one is likely on two legs while the first one is on four. I think it is teasing two pokemon. But man that got dark....
Also the time frame of a video camera being invented is around 1888. So I think we now have our time period.
Edit: It could possibly be a Poocheyena. IN Pokemon Snap, we saw Mightyena in the snow area. So it could be a Dark/Ice type.