Yes Safari on Windows was discontinued years ago and has no support for modern techniques. It’s like testing on IE6 and saying the site doesn’t work. There are probably less that 0.00001% of users using it and they are probably only misguided developers
Generally (not always) if it works on Chrome then it will work in Safari as they use the same engine.
There are however many subtle differences on the mac operating system that may affect layouts and can only be tested on those systems. Luckily though (if you have followed good coding practices) then you will find chrome on PC works much the same as Chrome on mac (ignoring os styling etc).
Paul, If you have time and patience, could you have alook at the code governing these images and let me know if there is anything wrong/missing/excessive?