Team for Blake at this point in your story
Dewott
Cinchino
Dieno (Dragon breath gave it away)
Darumaka
Swalloon
Drillbur
Kept some under evolved so you can evolve some of them in your story. Or not, it's up to you. Actually, We could scrap Darkumaka and have him feed a rage candy bar to the Darmanatan in zen form by accident and they help deal with the big pokemon reported. And he could catch one of them.
(P.S. imagine if the big pokemon is a big Dragonite situation lol. Like that one episode in indigo league with the big ass Dragonite?)