جَاءَنِي بَعْلَبَكُّ — Baalbek came to me.
جَاءَ: past verb.
نِ: protective nūn (nūn al-wiqāyah), with no syntactic case position.
ي: attached object pronoun, accusative position.
بَعْلَ: first component of the proper name, built on fatḥ.
بَكُّ: second component with visible nominative ḍammah; the whole name is the subject.
Only the second component takes nominative ḍammah; the first stays on fatḥ.