I am seeing similar results with my current 1809 build in the lab as well and it's even varied between two separate Gold images.
On both images the Logon monitor service is automatic and shows running but does log properly in one pool while the other the log files are not creating appropriately. Then if you go into the newadmin tool and look for the session details only limited data is there.
Not an answer but validating that you're not alone.
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Joe Graziano
Senior Solution Engineer - EUC Federal
VCP7-DTM, VCP6-DM, VCP6-DCV
vExpert, vExpertPro
jgraziano@vmware.com