Nothing to watch out against. You're referring to a simple dockerfile for convenience of testing and displaying configuration options, while neither Grafana or Minio are part of IOx or the community builds.
InfluxDB 3.0 Infinite Observability with qryn-iox · HackerTrans
That said, influx_iox itself appears to be Apache 2 (and/or MIT?) https://github.com/influxdata/influxdb_iox/blob/main/LICENSE...