They were related, the Enrico you are talking about is the grandson of the Infanta's husband. The link is as follows:
Infanta Maria Cristina was the second wife of widower Enrico Marone-Cinzano. From his first marriage, Enrico had 3 children: Rosanna, Consuelo and Alberto.
Alberto, 2nd Count Marone, married Fiat heiress Cristina dei Conti Camerama (great granddaughter of Giovanni Agnelli, the senior) and had 3 children: Noemi, Francesco and Enrico.
Enrico dei Conti Marone-Cinzano married Princess Mafalda of Hessen-Kassell (granddaughter of Italian Princess Mafalda di Savoia) on 1989; the marriage lasted less than 2 years and they divorced on 1991. Princess Mafalda married secondly Carlo Galdo and had 2 daughters and thirdly Ferdinando dei Conti Brachetti-Peretti and had 2 sons.
Upon the death of Count Alberto on 1989, the title was inherited by his elder son Francesco, who is now the 3rd Count Marone.
As a result, Infanta Maria Cristina was the stepgrandmother of Enrico dei Conti Marone-Cinzano (the younger).