for any Auth Related events such as Authentication and session Validation , we do not see the Transaction ID printed in the smaccess log as indicated below regardless if we have enhanced auditing enabled or not
ValidateAccept CB1016168 [15/Sep/2021:09:34:25 -0400] "x.x.x.x CN=joseph rahme,OU=support,DC=com" "agent-name POST /test_url" [idletime=3600;maxtime=515774530;authlevel=5;]   
and as you can see from the policy Server trace , a Transaction ID was Passed by the Agent but we did not Print it --> [000000000000000000000000a71a7844-3f81-6141f5fb-0063-150c16e3][Receive request attribute 221, data size is 60]
Release : Any Siteminder release
Component : SITEMINDER -POLICY SERVER
This per Design.
In case of Authentication events, Session related information is getting printed instead of the Transaction ID.
Session related information like [idletime=1200;maxtime=515770761;authlevel=5;]
In case of Authorization events, transaction id is getting printed as is.