Messages from Softaculous get blocked if a reseller uses DKIM and DMARC records to protect their domains.
This is common sense these days and it's very annoying that only admin can send mail via SMTP and that Softaculous only uses php mail() for resellers.And maybe customers too.
That should not be the case. Every self-respecting modern script should have the option to use smtp-auth when necessary.
Please add this to Softaculous for resellers too for notification messages at least.