Question says it all. Also, don't tell me to battle in the E4 because it isn't strong enough to beat them(I'm in postgame). The Dodrio is level 62 too.
Arguably the best trainers for grinding your Level 62 Dodrio is Cooltrainers Michelle and Leroy in Sevault Canyon. These 2 trainers combined yield the most experience in the game of 20,239 EXP. In addition to this, they are right by the Chansey Dance house for you to heal up your team as well. The only Pokémon for you to worry about are Leroy's Slowbro and Michelle's Girafarig, but you are still 8 and 6 levels higher than both of them. Because of this, easy healing, and the highest amount of EXP through the VS Seeker being obtainable here, I say that this is the best location. Source: https://www.dragonflycave.com/kanto/frlg-vsseeker#trainingspots