I have concluded that given is a ditransitive verb, therefore, grammatically there is a subject, a direct object and a complement. Correct?
You re correct that there is a subject, a direct object and a complement, and also that gave is a ditransitive verb in most contexts. However, passives make things tricky (your example is a passive sentence). Effectively, they demote the transitivity of the verb (and therefore the sentence): Fred was fired demotes fire (normally a transitive, as in Mr. Slate fired Fred to an intransitive, with only one argument); and your example demotes give from ditransitive to transitive (with two arguments and a complement).
