"Oh yeah, now it rings a bell, indeed WGS one does not have the gamble (havent played Doctor LOve for quite a while). Now that I think of it, WGS one seems different than all others and looks like Cryptologic one I played long ago (it even has that sounds when spinning). Layout and menu seems different as well. With the game being as old as it is, its hard to tell why the difference exist.
Nextgen is now under the ownership of NYX so all of their games have the same looking menu, and most of their games feature gamble option. But since Doctor Love predates all these re-brandings and merges, that may explain noticable differencies."