This confirms you have the correct file.
All I can think is that one of two things happened. Either you did not boot this particular OS, or you saved the dmesg under a different name. I'm going to guess the latter, but you can check:
You can confirm you are running that kernel by watching the dmesg as it scrolls by (if you use -c, it will stop for UKC> and you can inspect it without having to be a speed reader), or, you can confirm it after logging in with:
$ sysctl kern.version
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