Nah. I don't buy that at all.
TOGA thrust on a 738 produces a massive surge in power and pitch up. There is no way a competent pilot could take control and not notice, let alone hold the thrust levers shut against the servos and not notice, and nor is it feasible that a pilot of any experience level could fail to notice one engine producing max reverse thrust while the other is producing TOGA thrust; the yaw shortly after touchdown would be massive and they would have exited stage left far earlier in the landing roll if that had occured.