Regarding the first issue where on logging to Informatica Analyst "human Tasks are missing", message occurs when the Workflow engine in the DIS is not initialized.To resolve the issue, ensure that the workflow engine is running by reviewing the DIS logs. Refer https://kb.informatica.com/solution/23/Pages/63/519587.aspx for more details on this.
Even though the DIS is initialized, the workflow engine will take longer to initialize and hence the issue.
Regarding the second error logs snippet, for the logs related to Analyst service in the Admin console please note that these logs do not have any functional impact and can be safely ignored. Below are the repeated messages in the logs which can be ignored safely.
infa.model.RESULTSET_CRITERIA_SUPPORTED: Result set not found