most likely due the age of the game and they already planned for Rance 4 remake
I admit that I never really looked at the original release dates for both games until your comment and I have to say I am quite surprised.
2002 for Escalayer were I thought that was released at least a few years later than that and Haruka being from 2008 with me thinking it was a few years older.
One really does lose track of time in one's old age it seems.