The PAC "consultant" who brokered the deal proposed using as a conduit a type of organisation he admitted is seen as being responsible for the "'dark money' in politics".
The disclosures also highlight the apparent desperation of Trump's supporters to finance his campaign amid a series of controversies and polls showing him losing in key states.
Trump once labelled Super PACs a "disaster" that have "total control of the candidates", and has criticised Hillary Clinton for relying on outside groups.
Undercover reporters posing as consultants acting for a Chinese benefactor approached specific pro-Trump and pro-Clinton fundraisers and groups after receiving information that individuals were involved in hiding foreign donations.
Sources also said PACs, "independent" organisations that can raise unlimited sums of money to lobby for or against particular candidates, were being used to circumvent rules.
The pro-Clinton organisations did not respond to initial approaches.
This month an undercover reporter spoke by telephone to Eric Beach, co-chairman of the pro-Trump Great America PAC, which has the backing of Rudy Giuliani, a Trump adviser, and the billionaire's son Eric.
The reporter said a Chinese client wished to donate to the PAC to support Trump's campaign. Beach appeared interested despite raising concerns about his nationality and saying he would need to know the donor's identity.
He said the donation could be put through a social welfare organisation called a 501(c)(4) - or C4 - which unlike a PAC is not subject to a ban on receiving foreign money, and not required to name donors.
He stressed in an email that "any path we recommend is legal".
The reporter received an email from Jesse Benton, a senior figure at the PAC until being convicted in May in connection with buying a senator's endorsement.
He said he was a "consultant" and Beach did not want a "paper trail" of contact. Benton proposed channelling the donation through his own company to mask its origin.
It would be passed on to two C4s before being donated by them to the PAC, or used to fund projects planned by the PAC.
Benton said the US$2 million would "allow us to spend two million more dollars on digital and TV advertising for Trump".
The benefactor's generosity would be "whispered into Mr Trump's ear". Beach said at the Las Vegas event: "Trump knows that you know... there's no way that this group won't be remembered."
Yesterday Benton denied "unethical" behaviour. He said he spoke to the reporters after a "business referral" from Beach and that his firm had said "money could not go into a 501(c)4".
Dan Backer, counsel to the PAC, denied Beach asked Benton to act for him and said Benton "has not had a role with the PAC since May". The "referral" was so that "Mr Benton could explore legal options for your reporters' alleged client".
He said "the PAC has never... solicited or accepted contributions from a foreign national or entity" and said Beach was suggesting how "a US company with a foreign parent company could potentially engage in legal political activity".
Super PACs 'Independent' electoral funding
1 Super PACs are registered political action committees that can raise unlimited sums from individuals, corporations and other groups and make "independent" expenditures in US federal elections, as long as they are not coordinating with candidates or parties.
2 The system, introduced six years ago, has prompted fears donors could use it to mask their identity.
3 It has been claimed 501(c)(4)s, a tax-exempt "social welfare" organisation, can channel illicit funds into campaigns.
