Goliath died outside of Jerusalem, too, not Rome. And his people were Greek, not Roman, so it’s not like his remains would be taken back to Rome. And if he really was such a champion, his remains wouldn’t be left in a random forest with no marker or ruins about.
EDIT: No time for the old “Philistines aren’t Greeks,” love, I’ve just come to read the meter.
Goliath was a Philistine, not a Greek. Philistines were Semitic peoples and, at the time of the original story, probably would have followed the Canaanite religion that Yahweh was still a pantheon member of.
Bonus Fun Fact: Philistine is the etymological origin of Palestine.