To wash their hands of any potential fraud, IGG would have to stay out of every transaction completely. This would put them in the realm of a Common Carrier (US / Canada laws, probably many other countries are similar). If they ever were named in a lawsuit, they would quickly get them selves removed as a defendant by arguing that they only facilitate the communications between two parties, the campaigner and the funder. They allow them to "connect" in text, and communicate with each other, and they do not monitor, regulate or censor those communications. They are going to argue they are immune, like the phone company.
A person can commit fraud over the phone, with multiple victims. The phone company is a facilitator of that fraudulent act. Yet the phone company is always immune from prosecution for fraud. I think IGG will always stay out of the loop. Once they intervene, if only one time, then they are open to multiple lawsuits. Actually, in my opinion, and I am not a lawyer, I think kickstarter is more liable for campaigns on its site, than IGG is right now.
(I don't condone fraud, nor the projection watch here which seems rather implausible to me)