Yeah they do and i'm pretty certain that will be confirmed this arc. You'd see Neko and Jack using haki, likely Ace as well in a flashback considering the parallel Oda already created with Luffy - Ace - Tama and the rescue Wano plot
Inuarashi is confirmed to have haki and Nekomamushi is his equal. Unlikely he doesn't have haki. Jack could clash with both of them, even while they alternated every 12hours. Unlikely he didn't have haki to counter Inuarashi. Ace fought a veteran haki user(Jinbei) as a rookie. Unlikely he doesn't have haki.
People levels below them displayed haki, and Ace even awoke conqueror haki at 10, was Roger's son(pirate king's son), with potential feared by the entire world government