Thanks. The first one is the one we're after:
[2019-09-26T11:55:27,652][INFO ][o.e.c.s.MasterService ] [node-02] node-left[{node-00}{A9AdXLb5QA-ZMcicCn26OQ}{S9uJF_S1QNC1SsgTqmY3bQ}{10.1.3.110}{10.1.3.110:9300}{dim}{ml.machine_memory=134928560128, ml.max_open_jobs=20, xpack.installed=true} lagging], term: 3, version: 2093, reason: removed {{node-00}{A9AdXLb5QA-ZMcicCn26OQ}{S9uJF_S1QNC1SsgTqmY3bQ}{10.1.3.110}{10.1.3.110:9300}{dim}{ml.machine_memory=134928560128, ml.max_open_jobs=20, xpack.installed=true},}
Note the lagging - this means this node took more than 2 minutes to process a cluster state update, which Elasticsearch 7.x treats as a failure of this node.
The logging around this is improved in 7.4 (and even more in 7.5) but in 7.3 I suggest you add
logger.org.elasticsearch.gateway.MetaStateService: TRACE
logger.org.elasticsearch.cluster.service: TRACE
This will give much more detail about why it is processing cluster states so slowly.