I'm not accepting multiple i3lock forks in the repository, as per my notes here. i3lock-color was intended to replace i3lock directly (changing the source), however it had segfaults and memory leaks, so I reverted it.
Either way, using i3lock with Budgie is not supported. The officially supported screenlocker is budgie-screensaver, a fork of gnome-screensaver. This was originally done because GNOME effectively refused maintainership offers by Ikey of gnome-screensaver, they wanted to kill it instead. For Budgie 11 I'd rather lock be integrated directly into the window manager.