Door to the Unknown: Fantastic Dual Sudoku!

Today's Puzzle:

A fantastic puzzle from Will Power that almost gives us some insight into how these puzzles are constructed with two possible solutions dependent on a single rule.

Link to Play:

Door to the Unknown by Will Power https://tinyurl.com/SudokuSleuthDoorToTheUnknown

Rules:

Normal Sudoku rules apply.

X PAIRS- Numbers with an X between them sum to 10.

KROPKI PAIRS- Numbers with a white dot between them are consecutive. Not all possible X and dots are shown.

KILLER CAGE- First, Solve the puzzle with the numbers in the cage summing to 7. Write down the three numbers in row 1, box 1. Second, Solve the puzzle with the numbers in the cage summing to 13. Write down the three numbers in row 8, box 7. The solution code in Logic Masters Germany is these 6 numbers. The pink coloring is the door, and has no effect on the puzzle.