On firmware: no, loading a firmware extension doesn't trigger anything. Loading a module extension does.
However, it's safe to load them on boot in any order, since on boot the actions (such as triggering due to modules) happen only after all extensions are loaded; ie, when both the firmware and the wireless modules are available.
If you have included wireless modules in the initrd, you'll also need to include the firmware, as in that case they're not in an extension anymore.
edit: Oh, it's a wired module, not wireless. Anyway, you can do a manual trigger in bootlocal.sh if you like: "udevadm trigger".