Ok you battery cell is nuked.do not try to re-use that sucker you might not have any time left to run.
Then if your positive pin moves up and down then your mod should be fine.the battery took the punishment in this case.
Now you need to heat the plastic with a hairdryer or heatgun but you need to be carefull with a heatgun it could ruin it more then try to push the plastic back down to fit the battery.
I hope this works for you.
Personally i have never experienced issues with shorts and such however on my mech batteries even though my pro mech has a delrin insulated sleve around where the battery sits in the mod to prevent shorts i always make sure my wraps are in pristine condition. For my vw mods im not too bothered but replace them when desperately needed.
Batgery wraps are inexpensive if you go for the plain ones or superhero ones which ive seen go at SirVape for R10 or so and Vapera Corner for R15 however if you want to splurge you can get a cool OBD wrap for about R50 a pair.
All in all its cheap and easy to install all you need is a hairdryer and a minute or so. And in the end it could save you hundreds if not thousands of rands... a finger or two... maybe even half of your face.
Play it safe. Always use protection and check for holes before use.