Hi,
You need to update jQuery version on your site.
Icegram works on jQuery 1.9 and above and jQuery installed on your site is 1.7.1, that’s why icegram campaign is not loading.
Either jQuery 1.7.1 is getting loaded from Legend theme or from some active plugins.
I recommend you to use jQuery 1.11.3 as wordpress is also using and we follow wordpress.
If you have a staging site then first update jquery version on that and once you confirm that everything is working fine then update it on live site.
Note: Once you update jquery version on your site then please check all the features because sometimes it may happens that due to incompatibility with latest jquery version some features may break.
Thanks,
Nishit Shah
Team Icegram