There's a few good ways to increase back grapples for finishers -
1. Opp. Dazed, shift some of the front grapple percentage to back grapples
2. Opp. Down, turn over when on back more towards end of match, higher chance to lift up when face down
3. Add the back switch move as a front grapple in small damage, set logic to something like 5/10/20
4. Use the back switch counter to back grapples

Up to you on the move percentage used, depends on how often she's able to get back grapples off. I like to use ~40% in the highest damage category for a back grapple finisher as it's a tougher position to get into naturally.

Thanks for the reply. What logic changes would you recommend and what move should replace the front grapple version? Thanks.

https://firepro-w.com/item/detail/188205

Reddit post showing his process: https://www.reddit.com/r/firepro/comments/nma2wx/making_toni_storms_ruby_ddt_in_move_craft/?utm_source=share&utm_medium=ios_app&utm_name=iossmf

There’s a ton of custom frames, would take a ton of time to export a move into a text format, and probably even more time for someone to implement all that. I know Miguel-F made a version already, but it might be a back grapple. If so, the logic would need to be changed to put her in position behind her opponent more in order to get the finisher off the right amount

Any chance of this move being ported to PS4? I'm looking to port over some of your edits (for personal use) and having their custom moves/parts would help greatly.

That was fast!