What does "it" represent in the following sentence?

I read the following sentence on the leading corporation in a corruption-infested country.

Its path to the top was strewn with secret deals, price fixing, bribery, tax evasion and more, all of it overseen by an ultrasecretive, ultrarich family ready to use every means at its disposal to stay in command.

What does the pronoun "it" refer to?

Given the pronoun "it" represents a singular noun, logically, "it" in the sentence apparently refers to "its path to the top." But the phrase "all of it" somehow sounds plural.

Solution 1:

It means that all of the cheating (price fixing, secret deals etc...), were overseen by ultrasecretive, ultrarich family.

So the sentence should look like:

... all of the cheating overseen by an ultrasecretive, ultrarich family...

Solution 2:

"All of it", in this usage, refers to the preceding phrase:

secret deals, price fixing, bribery, tax evasion and more . . .

Sometimes, when I am editing for greater clarity, I will replace an "it" with what is referenced by the "it". In this case, that might give you something like this:

Its path to the top was strewn with secret deals, price fixing, bribery, tax evasion and more, all of it (secret deals, price fixing, bribery, tax evasion and more) overseen by an ultrasecretive, ultrarich family ready to use every means at its disposal to stay in command.

A bit cumbersome, but it might help in understanding the usage. The items listed are multitude, and uncountable (or uncounted), thus "it" works. One could also replace the "it" with "them", but not "that", or "those", as the items categorized in the list are not exclusively singular or plural.

Because of the multitude of "its" in the sentence, if I were editing it, I would replace the "all of it" with "all of them".