Trouble logging in with a dead display - is there a way to force screen mirroring?

My macbook Air 2019 has a dead display (confirmed by an Apple Store). They indicated I could plug in a monitor to get access, copy data off, etc. Note I tried all the hacks to get the screen working (including pram reset)

When it boots normally, the keyboard lights, and I get no external display. I tried command-fn-1 (note: nothing shows in the bar above the keyboard), no luck getting the display to work.

If I force a reboot (hold power 5s), and then press power, the external display comes on and it goes into the recovery assistant. I have to semi-blindly get through language screen, and the login problem options come up on the external screen. I have the password to one of the accounts (I forgot the admin account password, it's my daughters machine). I don't want to change that password though. I select Forgot my password, and give my AppleID and password. That gets me to a Terms and Conditions page, which I'm stuck at -- it won't let me agree.

Is there a way to force the external monitor into mirroring without being able to see what it's asking on the internal monitor? I don't have a USB-C keyboard or mouse; I have some USB-A keyboards and mice. I do have a multiport adapter I'm using to get HDMI out; I could plug USB-A keyboard and mouse into that.

Thanks!