Multiple possible solutions, even when assuming there's some symmetry involved. The hints below are for the top left corner, but I think the rest of the puzzle can be solved by applying the same pattern. Reminder that the hints provided by the author are for 5x5 sections, not single squares.
**SPOILERS**
R3 C3 ; R4 C4 ; R5 C5 ; R7 C3 ; R8 C8 ; R9 C5 ; R10 C10 ; R13 C1 ; R15 C5.