Different lightning cable?

You need to look inside of your iPad;'s Lightning port, with a light source, and use something thin, stiff and non-metallic and see if you can clear out any loose pieces of plastic from your old cable connection end that maybe still caught inside of your iPad’s Lightning port that maybe hindering the new cable from being able to be inserted.

Good Luck to You!

The Lightnng cable connector end on the left hand cable looks wrong or broken ( no plastic edge boundaries around the metal connector part.

Is it possible part of plastic around the connection end of your old cable connector end broke off and is still stuck inside of the Lightning port of your iPad Mini 2?

It sure looks as if this is what has happened.

A part of the plastic surrounding the metal connection end on the left hand cable looks like it broke off and maybe still lodged inside of your iPad's Lightning port.

This may explain why your new cable does not fit.

Part of the plastic of the old cable is stuck inside of your iPad's Lightning port.

Did you try plugging it into your iPad Mini 2 to see if it works and charges your iPad?

All of my Lightning connector male ends look like the one in your image on the right and they all work fine with all of my Lightning port iPads.

That cable on the right should fit.