  In 1994, van Geemen and Top constructed a non-selfdual motive of rank three
over $\mathbb{Q}$ conjecturally associated with a cuspidal non-selfdual
automorphic representation of $\mathrm{GL}_3(\mathbb{A}_{\mathbb{Q}})$ of level
$\Gamma_0(128)$. They experimentally confirmed the coincidence of the local
$L$-factors at finitely many primes using computer. In this paper, we shall
prove the coincidence of the local $L$-factors at every prime. To show this, we
use the recent results of Harris-Lan-Taylor-Thorne and Scholze on the
construction of Galois representations, and Greni\'e's results to compare
three-dimensional $2$-adic Galois representations. We also prove the
local-global compatibility at $p = 2$, including the case $p = \ell$.
