I think he means that part of the Dex that says how Dreepy gets stronger with the help of friends but really that's just flavor text anyways...
So far this saga is faithful to the dex entries, so I see no reason for the writers to rule out Dreepy receiving help from Dragonite and Core-Gengar.
In the episode Go caught a Taillow and 3 Wurmple, he mentioned the Tiny Swallow Pokémon preys on Wurmple so he used it in order to find Wurmple, in the episode the Wurmple trio evolved, Taillow tried to eat them.
In the episode Ash caught Dragonite, the species saved Ash and Go from drowning while a Dratini was seen shedding its skin.
In the episode where Core-Gengar made its debut, it was chilling its surroundings and later on its capture episode it was hiding in Ash's shadow.
In the food shortage episode, Go's K-Farfetch'd considered eating its leek but quickly choses against it, because its dex entries says that its leek is not only a weapon but also a food source for dire situations and when it eats its leek, it will desperately search for another one.
And in the upcoming episode they're being faithful with Flygon's desert spirit dex entry.