You need to install the Couchbase server on the machine, and extract the PDB zip file (I've put it in C:\Symbols). After installing the server you might want to stop (and disable) the Couchbase service.
Open WinDbg (64 bit); if you don't have it available on your machine you can get it as part of the Windows SDK (I failed to install the standalone package). With the minidump file loaded in WinDbg you need to tell it how to locate the PDB file for memcached:
.sympath+ C:\Symbols\couchbase-server-enterprise_7.6.4-windows_amd64-PDB\build\kv_engine
Then tell it to reload the information
.reload /f
With all the symbol information available it is time to analyze the crash:
!analyze -v
And you may fetch the callstack for all threads
~*k
Then save the output (there is an option to save the content in the menu) and feed it to Gemini.