There are notable differences between this thread and the other one you referenced, however. The most important difference is that according to a recent poster Pierce County District Court does not usually have a prosecutor for infraction hearings. That poster got an attorney who apparently wins more easily there because there is no prosecutor. So in this case nobody will be in court to present a more recent certificate.
The other difference is that the poster for this thread got an expired cert included with discovery materials, whereas the former poster was instructed in discovery to look it up at the court then got blindsided by the prosecutor. His attorney plus one on this forum are inclined to think he will win on appeal.

