'bop_sinfo' to the rescue...
The 'action on true' macros are linked through 'lrel_true_action_act_t'. The schema name for that is also revealed by 'bop_sinfo':
So you can join to 'usp_lrel_true_action_act_t' in the database using the event id to find the 'action on true' macro id's, and join again to 'splmac' to get the macro names.
Hope that helps.