How so?
Wiemer is an elite hitter against LHP, so you're not taking him out. Tyrone Taylor, who played RF, has a career OPS vs. LHP in the majors of .725, which is a lot better than Frelick's in the minors this year. DH wasn't an option either that night as Contreras needed to be in the lineup with Caratini catching Burnes.
They're playing him fine.