Do you have access to the DB? If so, I think the following should work. I'm not sure if there are any OOTB relationships to use but you could probably create one between "Employee" and "Frs_ops_logon_history" to do the same through Heat.
select LoginID, max(LoginTime) as 'Date/Time'
from employee e
join Frs_ops_logon_history lh on e.LoginID = lh.UserId