[Grammar] Is this paragraph phrased correctly?

[motico]

Is this paragraph phrased correctly? (Especially the conditional)
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If you really engaged in fighting wrongdoings in the company (which nobody can deny their existence), many would joined you. But the unpleasant fact is that you are taking part in a campaign which aims at discrediting our company's reputation.

 

[Tdol]

(which nobody can deny their existence)- How about (and nobody denies that they exist)