If I hold a sneeze (or many sneezes) is there any way that my eyeballs could escape my skull?
No.
But by doing so, the back pressure could drive mucus deep into your sinus cavities. If you already have some sort of nasal ailment, you could be making it much, much worse.
Besides, why hold a sneeze in the first place? By definition, a sneeze is your body’s way of getting rid of an irritant. You want to keep irritating your body? 
I hold in sneezes b/c I don’t always have 2 tissues in front of my face. If I did, then i wouldn’t have to worry about baptizing the computer, keyboard, and monitor with snot.
So sneeze with your mouth, then go blow your nose.
There’s also the trick where you hold your eyes open to halt the sneeze response, but I haven’t tried it.
if you sneeze hard enough (and have especially labrynthine sinuses) and plug it, you could rupture a sinus.
still, i hold mine. sometimes it’s the only option.
the eye trick never worked for me; however, i also exhibit the photic sneeze reflex. the one trick, oddly enough, is the ol’ cartoon standby. yup, the finger pressed under the nose.
jb