I wish it were subtitled, but the comments on YouTube reveal that the closing line is "That monster will never forgive us."
I was easily able to understand "Is that... Godzilla?" in the shot used as the screencap. Which is interesting, since this is set in the '40s, so how is Godzilla already known? Well, maybe the scene is from later in the movie after news of Godzilla's emergence has spread.
Hearing the announcer say "Gojira Mainasu Wan" at the end made me think of something. I've been taking the title to be a reference to "T minus one," like a countdown, since it's set before Godzilla's traditional 1954 debut. But the Japanese use the English loan word "minus" to mean "negative," for instance, "minus energy" for "negative energy." So it could also be interpreted to mean "Godzilla negative one," especially since the logo is written as "G -1.0". I don't know if that means anything, though, unless it's just another way of expressing the idea that this is before the original Godzilla. (Which would make the 1954 one Godzilla Zero, which kind of works, since most continuities center on a second Godzilla that emerged after the original one died, either briefly thereafter in the Showa series or decades later in the Heisei series and most of the Millennium films, with the exceptions of Megaguirus, where the original's death was retconned out, and GMK, where the original had nearly died but regenerated.)
