That's an excellent observation. Reading from what Wikipedia has to say about Poi Dogs. They were (sadly) also considered lucky charms. A dark origin for a potential pokemon... but it could it explain the jewel 'Colar' around the unidentified pokemon
Damn, you're right.
The Poi Dog especially looks like Much Wow Doge (that's what I'm calling it). The most striking feature is the curling tail.
Right and in fact, as I just noticed Rampharos (who also suggested the Poi dog before me) has also suggested. It could be a good way of Gamefreak giving us a sort of Furfrou mechanic but rather than it being based on grooming. It instead could be linked to the whole Idea them being a good luck charm. So regardless if it is a jewelled collar or a Lei the colour could also represent and therefore have a small, different effect in game. Like a visible amulet coin maybe?
My other reason (and possibly Rampharos' thinking too. I apologize if it is not in the event of you reading this.) Is that almost all of the Pokémon (except the Sun legendary maybe) we have seen so far are either native or can be found in Hawaii.
Litten: Feral cats are a fairly common thing there as are dogs which could also go towards this unknown Pokémon being a dog as well. Regardless of breed.
Popplio: Hawaiian Monk Seal is one of only two mammals native to Hawaii (i.e were not introduced or pass through during migration), the other being the Hawaiian Hoary Bat.
Rowlet Pueo Owl. Might be another type of Owl but they are a thing and also important to Hawaiian culture and folklore.
un named Moon legendary: Hawaiian Hoary Bat stylised because it is the Moon legendary.
Unknown bird Pokémon: Some people say it might be a Cardinal, but others say a wood peeker because of the feet and colouration (though it should be noted some Cardinals are also those combined colours). While it may not have the colouration there is a bird known as the Akiapola'au which is similar too and nick named as the Hawaiian woodpecker.
So this combined with how the back end of this yet un revealed Pokémon appears and given the Poi dog's history and relevance to Hawaii. I would be very surprised if this new Pokémon wasn't connected to them in some way.
I mean looking at some of the previous Pokedex entries going dark isn't too much of an issue provided it isn't too obvious to people below a certain age.