There's probably enough sugar in this recipe to be safe... but I think you can do this without the eggs. They're just there for added richness. Use a full fat cream cheese to make up for the lost eggyolks. I also think it's quite safe. You will need to double the whipping cream to come up with a similiar result.
Essentially you're making a frozen pumpkin mousse in a pie shell, served with warm chocolate fudge "sauce." If you want, you can look for a frozen pumpkin mousse recipe which doesn't use eggs if you're not comfortable with my suggestion above.

I think it will work though.
Edit: Notice you're making a meringue out of the eggwhite, but you're not cooking the yolks anyway.