Learn English – many/much fireworks

"Homage" is a countable noun, in the sense of "an act done in tribute of or respect for something". (in fact it's the usual meaning of the word nowadays)

An entry, showcasing meanings and different pronunciations

Also, the reason why the writer put an before "homage" is because the pronunciation of homage is kind of all over the place, with some pronunciations having the H silent.

Sugar is uncountable: grains of sugar are countable.

Air is uncountable: oxygen molecules are countable.

Money is uncountable: dollars are countable.

Sometimes we want to use a collective term for stuff that you use to buy things with- that's money. When you want to start quantifying (counting) it, you have to use a currency- dollars, dinars, yen, euros.