If doge-dice gets alive again then it will survive, but without it, it is gonna be hard...
You can invest DOGE on
prcdice.eu (you can switch between BTC and DOGE), also on
dogeking.comObviously neither of those 2 is anywhere close to DogeDice in terms of size and popularity.
EDIT: If anyone knows any similar sites when you can invest DOGE please share