Issues with licenses and installing Pro

They were not running 2.7.0 to start - I actually didn't make a note about which version the first one was running, but the second one was definitely on 2.6.4 when I tried to run activate-license. I extracted the curl command run by the script to see what the issue might have been, which is where I saw this (Serial and Licenses redacted):

root@tinypilot:/home/pilot# curl https://gk.tinypilotkvm.com/pro/download/2.7.0 --location --get --data-urlencode licenseKey=$LICENSE --data-urlencode machineId=$SERIAL --header 'TP-License: $LICENSE  --header 'TP-Device-Serial-Number: $SERIAL' --output /mnt/tinypilot-installer/bundle.tgz --write-out '%{http_code}'
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100    29  100    29    0     0    241      0 --:--:-- --:--:-- --:--:--   245
403

root@tinypilot:/home/pilot# ls -al /mnt/tinypilot-installer/
total 12
drwxr-xr-x 2 root root 4096 Apr  1 01:03 .
drwxr-xr-x 3 root root 4096 Apr  1 01:03 ..
-rw-r--r-- 1 root root   29 Apr  1 01:03 bundle.tgz

root@tinypilot:/home/pilot# strings /mnt/tinypilot-installer/bundle.tgz
License key is not activated

In the original command line the $SERIAL and $LICENSE variables looked legitimate to me. The $LICENSE one was copied directly from the license-check web form, and was the one that worked when I reinstalled 2.7.0 directly. That's about all the info I can provide at this point, though, most of it has been lost to the gods of scrollback buffer limitations, unfortunately.