"API error occurred: user_not_found" due to user U00

[langabi]

Getting error like this:

Downloading info for user U00.../Users/paulcook/.npm/_npx/857523a31d18f748/node_modules/@slack/web-api/dist/errors.js:56
    const error = errorWithCode(new Error(`An API error occurred: ${result.error}`), ErrorCode.PlatformError);
                                ^

Error: An API error occurred: user_not_found
    at platformErrorFromResult (/Users/paulcook/.npm/_npx/857523a31d18f748/node_modules/@slack/web-api/dist/errors.js:56:33)
...

See specifically the user ID is "U00". A google found page https://github.com/zulip/zulip/blob/main/zerver/data_import/slack.py which includes comment:
# Skip messages involving the the "U00" user,
# which is apparently used in some channel rename
# messages. It's likely just the result of some
# bug in Slack's export system. Arguably we could
# change this to point to slackbot instead, but
# skipping those messages is simpler.

So I guess this needs to be done here too. Will try to find the relevant code, but I'm not a typescript expert, so other help much appreciated!