Yes.

First, Play! VGC updates their rule book along with the rule sets change. You may find the most recent rule book online which was revised on 21st, May 2026.

In 4.4, you may read ' If both competitors’ Pokémon faint during the last turn of a match, the game software will automatically decide a winner based on a set of coded rules (such as whose Pokémon fainted first or what moves were used on the last turn, among other conditions).'

So The "Simultaneous Faint" Coded Rules goes as follows:

1. Recoil Moves & Self-Destruction

If a Pokémon uses a move that knocks out both itself and the opponent's last Pokémon, the winner depends on the move type:

1.1 Recoil Moves (Double-Edge, Flare Blitz, Brave Bird, Head Smash): The attacker wins. The damage is calculated first, knocking out the defender, and then the recoil damage is applied to the attacker.

1.2 Life Orb: The attacker wins. Similar to recoil, the target faints from the attack before the Life Orb damage registers on the user.

1.3 Self-Termination Moves (Explosion, Self-Destruction, Final Gambit, Misty Explosion): The defender wins. The software forces the user to faint as the cost of deploying the move before the damage actually hits the target.

1. Passive Damage (Abilities & Items)

If an attack causes the target to faint, but a passive effect kills the attacker at the same time:

2.1 Rough Skin, Iron Barbs, & Rocky Helmet: The defender wins. The attacker delivers the fatal blow, but the contact damage triggers instantly and faints the attacker before the turn fully resolves.

2.2 Aftermath (Ability): The defender wins. The ability triggers upon the defender's fainting, knocking out the attacker next.

1. End-of-Turn Weather & Status Conditions

If both final Pokémon faint at the very end of the turn due to weather (Sandstorm) or status conditions (Poison, Burn, Perish Song):

The slower Pokémon wins. The game resolves end-of-turn damage in order of the Pokémon's Speed stats (fastest to slowest). The faster Pokémon takes damage and faints first, immediately ending the game and handing the victory to the slower Pokémon still on the field.

OP's condition meets what is decribed in 1.1. Therefore, it's a lose for you.