Why does it say "Kol Goyim"?
Radak: Nowadays, the Goyim err and serve many gods. There will be a time when they will all recognize that You made them.
Why will they bow to Hashem?
Radak: They will recognize that You are Master of everything.
Malbim: Those who said that there were partners in creating the world will not honor His name alone, for they think that there were also other creators. However, they will bow to Hashem, for no one conducts the world like He.
Why does it say "vi'Ychabdu Lishmecha"?
Rashi: Refer to 86:10:2:1.
Radak: They will not honor another other than You. This will be in the days of Mashi'ach -"v'Hayah Hashem l'Melech Al Kol ha'Aretz" (Zecharyah 14:9).
Malbim: Those who deny Hashem's conduct of the world, they honor Him, for He is the first Cause, but they do not bow to Him, for they think that He knows nothing of the lower world.