Totem Pokemon are said to be fought after "Each Trial".

Which are done by the Trial Captains.

I think this means that every Trial Captain will have their own Totem Pokemon at the end of their trials.

Totem Lurantis and Mallow's(grass type) trial are both taking place in Lush Forest.

If we take this into consideration, this means we have just as much Totem Pokemon as Trial captains, as well as push the fact that there is a Normal Type Trial Captain with Totem Gumshoos