Crazy! Maybe the non-BEL babies will provide some clues? If the male is a very low-expression Mojave Leopard, you may get a Mojave hatchy. Super curious to see what all come out.
I wouldn't rule out retained sperm from the Butter just yet. While she wasn't bred to anything in the in-between season, I have had a girl go three years after pairing and then produce a clutch. They can be very at keeping that stuff on lay-away.