Hi Badger,
Yes, that seems to be a likely fix for my issue. This is what I was also told on Github.
I will update the plugin on my logstash 7.11.1 and see if it works. If it doesn't I'll repeat the plugin upgrade on 7.13.3 (The released version of logstash-integration-kafka for 7.13.3 seems too old to incorporate that fix).
Thank you.