excluding regex does not work in dunstrc rules

[BadgerAAV]

Issue description

I use batsignal to notify of a low battery on my laptop.
Dunstrc has two sections - for all notifications excluding the batsignal application and for the batsignal application itself.
With regex excluding only the batsignal application, dust writes in the log
WARNING: Invalid preceding regular expression: "^(?!batsignal).*$"
and does not process my script from "all" section.
If I remove the rule, then when receiving a notification from batsignal, both my scripts from the All and batsignal sections are processed, respectively.

Installation info

• Version: 1.9.2 (2023-04-20)
• Install type: extra/dunst (package)
• Window manager / Desktop environment: i3wm
• Distro: archlinux

Addition to the standard dunstrc

[global]
    enable_posix_regex = true

[all]
    appname = ^(?!batsignal).*$
    script = ~/.config/dunst/bell_sound.sh
    
[batsignal]
    appname = batsignal
    script = ~/.config/dunst/power_sound_alert.sh

Is it possible to use exclusionary expressions in the rules?
I want to set the rules for a separate script for one application and one separate script for all the others.

[fwsmit]

Moving to discussions to discuss possible regexes. Note that dunst uses the following line to compile the regex:
regcomp(&regex, pattern, REG_NEWLINE | REG_EXTENDED | REG_NOSUB);

You can take a look at man regcomp and POSIX regex syntax