Can't scrape Naomi and Atomiswave as a single system

[dodonpachi]

EDIT: I have a Pi 4 2GB running the official Retropie image.

So I created a custom system in Emulationstation for both Naomi and Atomiswave arcade games. My code in es_systems.cfg reads like so:

<system> 
<name>naomiatom</name>
<fullname>Naomi Atomiswave</fullname>
<path>/home/pi/RetroPie/roms/naomiatom</path>
<extension>.cdi .chd .cue .gdi .sh .zip .CDI .CHD .CUE .GDI .SH .ZIP</extension>
<command>/opt/retropie/supplementary/runcommand/runcommand.sh 0 _SYS_ naomiatom %ROM%</command>
<platform>arcade</platform>
<theme>naomiatom</theme> 
</system>

The games load and are playable, it shows up in Emulationstation, and it even matches my theme. However, I cannot successfully scrape any of the games with Selph's Scraper. I use that for regular arcade games, even with CHD folders, and it scrapes screen shots fine and hides the CHD folders. When I try to scrape my custom Naomi system, I get nothing--and it shows the CHD folders, as well as the actual Mame style filenames.

On Selphs Scraper, I use Arcade Italia for arcade games.

Any thoughts on what I'm doing wrong?

EDIT 2: I've removed the CHD folders by simply taking out the CHD extension in the systems cfg entry. Then I gave up and just used the built-in Scraper. It got the job done, but it doesn't use screenshots like Selph's Scraper. Oh well, better than before!