Ok, This is going to be a very “Hacky” solution, and I am not currently setup to do this myself (due to lack of ADSL at home) but I can provide a step by step guide of how I would approach this issue.
First of all you will need a tool called “Charles Web Debuging Proxy”
There is a tutorial on the site on how to enable “SSL debugging” in charles, (which will require you to install a new “root certificate” on your mobile device, to trick it into thinking that https transactions signed by charles are actually signed by instagram.com )
Now Set your mobile device to route all requests through said proxy ( which will have to be installed on your local wi-fi network.)
go to https://www.google.com and check that charles is logging both requests and responses.
Once this is all setup correctly then you can take a look at the API calls which the instagram app itself uses to generate said comment pages.