The PR in question:

googleapis/nodejs-bigquery-storage#209

The files from owl-bot are:

https://github.com/googleapis/nodejs-bigquery-storage/blob/48e92f43ea60ee20ca6e460ec59d74b458665406/system-test/fixtures/sample/src/index.ts

and

https://github.com/googleapis/nodejs-bigquery-storage/blob/48e92f43ea60ee20ca6e460ec59d74b458665406/system-test/fixtures/sample/src/index.js

You can see both files are using BigQueryWriteClient, but this is not the correct name, so the system tests failed.

I manually changed them to BigQueryStorageClient and now the system tests is passing.