SQL Failure I fail to diagnose seemingly caused by the service Broker

HI !

I have been using the service broker for nearly a year to trigger/parallelize some StoredProcedures / RServices machine learning tasks.

For a few days now, the workflow has been broken with these msg in the log

The activated proc 'procname' running on queue 'queuename' output the following:  'A system assertion check has failed. Check the SQL Server error log for details. Typically, an assertion failure is caused by a software bug or data corruption. To check for database corruption, consider running DBCC CHECKDB. If you agreed to send dumps to Microsoft during setup, a mini dump will be sent to Microsoft. An update might be available from Microsoft in the latest Service Pack or in a Hotfix from Technical Support.'

There are two error codes issued

Error: 3624, Severity: 20, State: 1.

A system assertion check has failed. Check the SQL Server error log for details. Typically, an assertion failure is caused by a software bug or data corruption. To check for database corruption, consider running DBCC CHECKDB. If you agreed to send dumps to Microsoft during setup, a mini dump will be sent to Microsoft. An update might be available from Microsoft in the latest Service Pack or in a Hotfix from Technical Support.

AND Error: 17066, Severity: 16, State: 1.

SQL Server Assertion: File: <tmpilb.cpp>, line=1816 Failed Assertion = 'SOS_Task::GetCurrent() == m_pTaskMain'. This error may be timing-related. If the error persists after rerunning the statement, use DBCC CHECKDB to check the database for structural integrity, or restart the server to ensure in-memory data structures are not corrupted.

* Location:     tmpilb.cpp:1816 * Expression:     SOS_Task::GetCurrent() == m_pTaskMain

We found and installed a related update for SQL2016 SP1 https://support.microsoft.com/fr-lu/help/4058565 with no change in behavior.

(Found this page too but it's for SQL2012 https://support.microsoft.com/fr-ma/help/3125526/fix-you-receive-error-messages-when-you-run-a-query-that-uses-tempdb-i so obviously not a solution for us)

DBCC CHECKDB returns no error

Thanks for your help.