There's no KillAura setting that makes every hit register — the module only aims and clicks, and the server decides whether a hit counts. On a server with a working anticheat, part of your hits getting cancelled is the anticheat doing its job, and pushing range/CPS up just gets you flagged sooner.
What actually helps is starting from a config built for the anticheat that server runs rather than hand-tuning:
Enable AntiCheatDetect and join — it prints the detected anticheat in chat. The anticheats page lists servers and their anticheats too.
.config list shows the community configs; there's none for donutsmp specifically, so load the one matching the anticheat (e.g. .config load grim) and use it as your base.
Settings reference: KillAura. Keep the range near vanilla — high reach is one of the easiest things for a server to catch.
Automated support reply. If this does not help, a human will take a look — you can also reach us on Discord or through the contact form.
