bug: this solver detects 2 solutions but other solvers only detect 1

080050600600000003500000081096507804100804005804209310470000008900000000001040070

![Image](https://github.com/user-attachments/assets/5735c06c-e58e-4806-a6b0-d64b373821af)

https://www.sudoku-solutions.com/

![Image](https://github.com/user-attachments/assets/50da8422-1cdc-4f9e-bbe9-e6cec18fc91f)