From the logs it seems an attempt to load the db records in the fixup function, which is executed after mod init callback, and typically the db connection is closed/reset in mod init callbacks not to be inherited on fork() for child processes, then opened in child init callback.
I split the error message in the srdb1 to be more clear in the future.
The recent commit to the module is cf2e3968000f1292ad1b1eb8f7d190fb53878c2b -- I am not familiar with the code, but I would look at the following snippet from commit to see if is the cause and/or done properly there:
* https://github.com/kamailio/kamailio/commit/cf2e3968000f1292ad1b1eb8f7d190fb...