Wow, thanks everyone for all the very imaginative answers.
When my insurance confirmed they would reimburse me for the whole value of the case, I thought I'd try anything so I took a knife and forced on the opening as hard as I could, which worked!
For the record I did try to warm up the case for the air to expand but it didn't work.
I've put the case in the water for 20 minutes, no leak so far so should be good
Thanks again for all the help!
When my insurance confirmed they would reimburse me for the whole value of the case, I thought I'd try anything so I took a knife and forced on the opening as hard as I could, which worked!
For the record I did try to warm up the case for the air to expand but it didn't work.
I've put the case in the water for 20 minutes, no leak so far so should be good
Thanks again for all the help!