Goryo's Vengeance and Veil of Secrecy
No, you can not

From the Comprehensive Rules (Ixalan (September 29, 2017))

Splice is a static ability that functions while a card is in your hand.
“Splice onto [subtype] [cost]” means “You may reveal this card from your hand as you cast a [subtype] spell. If you do, copy this card’s text box onto that spell and pay [cost] as an additional cost to cast that spell.” Paying a card’s splice cost follows the rules for paying additional costs in rules 601.2b and 601.2c



Seeing as the card is still in the graveyard, it's not a legal target for the Veil, and all spells you cast needs all its costs paid and legal targets (If it does indeed target anything.) before you can cast it.

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