Yeah that's how the airdrop tool works and the instructions use that tool too (the first step in the instructions just shows how to install the tool).
Several hours, flipping the code in many ways, such option doesn't seem to exist (and for sure isn't documented)
while (br.left()) {
const ct = br.readBytes(br.readU16(), true);
qqq++;
try {
out.push(key.decrypt(ct, priv));
} catch (e) {
continue;
}
}