Void Linux - Broadcom network adapter [14e4:43a0] appears, but will not connect to a network

Void Linux with kernel 5.9.16_1. I'm using NetworkManager on KDE Plasma 5.

Whenever I attempt to connect to a network with this adapter, Plasma says "configuring interface" for a while, and then it says "The WiFi network could not be found."

I installed broadcom-wl-dkms from the Void repo, and the device is using the wl driver. This allowed NetworkManager to detect the interface. NetworkManager can use it to see networks, but that's it.

Lines from sudo dmesg that I can tell are relevant:

This error is because there is no /lib/firmware/regulatory.db file. I installed dcma and there is a /lib/firmware/dcma/regulatory.bin file. I've looked and I can't find any packages that would have regulatory.db. I'm not sure where else I should look for it, or if I can somehow generate it from regulatory.bin.

Edit: I downloaded regulatory.db and regulatory.db.p7s from this repository and copied them both to /lib/firmware

Now this is what I get from sudo dmesg:

So it looks like cfg80211 is doing alright, either the necessary firmware is missing or isn't being loaded by anything. How do I get it to load the firmware?

I tried wpa_supplicant, but it kept printing wlp5s0: CTRL-EVENT-SCAN-FAILED ret=-22 retry=1 until I stopped it.