Every rise of a major player inevitably accompanies the fall of another.
Gao Guang didn't mind establishing his own notoriety in Baghdad by stepping on the Duhe family, not clinging to anyone's coattails or using another's reputation; he, Gao Guang, was ready to go to war with the Duhe family.
Gao Guang could ask many people for help; with the right moment, location, and support, he at least had the latter. Not to mention, Dawson could help, Moussa could also help, and even Kamile could lend a hand.
But while Gao Guang might seek their assistance, he definitely wouldn't let them take the lead, with him merely playing the role of a hired thug.