iPad 4 dead after hot air work

Hi guys

I recently purchased an iPad 4 cellular 32g with the wifi greyed out, on investigating the problem i found a shorted cap above the wifi chip C6101_RF i replaced it with the same from a donor board but using a hot air station at 300 heat, (i was a bit shakey with the soldering iron that day) I slowly heated that part of the board done the repair with a small nozzle all nice and tidy, I then for some reason in my thinking threw some heat a little further up the board for any dry joints as it had had a heavy drop in its life.

put it all back togeher and nothing no itunes recognition either, the battery was at full charge and checked that it still is.

If any of you guys can help me i would be very grateful

Thank you