However, the latest Zenith MD&A states the following: "As at July 31, 2022, we hold all 75,202,620 royalty preferred shares of Resverlogix." as already stated by RVXOT.
The MD&A also states that as of September 28, 2022, the number of common shares stands at 138,583,448.
If they are all RPS why is it that the totals above are not the same?

In 2013, RVX issued 75,202,620 royalty preferred shares to Zenith.  That number has never changed.  As RVXOldTimer just noted, ZCC owns them. So each ZHCLF doesn't have a royalty preferred share attached to it.  So as financings occur and new shares are issued by ZCC, the number of common shares (ZHCLF) goes up, but the N of royalty preferred shares never changes.  

If ZCC could unilaterally issue new royalty preferred shares, RVX would have to pay them more and more royalties.  I like it!  But unfortunately, not the case.

So again, all the ZCC shares are the same whether acquired in the 2013 spinoff or through a purhase of ZHCLF shares on the OTC or through a financing.