Manu Vunipola, who now works for the Ministry of Sport as a development officer, said he helped host a Welsh delegation which visited the kingdom this month.
Wales is scheduled to play Tonga next year but the venue of the match is dependent on the dilapidated Teufaiva Stadium being renovated in time.
If not, the fixture could be moved to New Zealand.
Vunipola said he was hopeful the game would still be held in Tonga after showing the visitors around.
"We went to the hospital, we went to the hotel," he said.
"They look around at the hospital, look around at the hotel, the training field and then we ended up at the gym," Vunipola said.
"They are happy at the gym too but the main thing I think for the visitors is Teufaiva but luckily they had a meeting with the Deputy Prime Minister [Siaosi Sovaleni] and I know they are really happy."
Vunipola said the group seemed to be satisfied with reassurances offered by the government.
He said a test in Nuku'alofa would continue the special relationship both Wales and Tonga have as rugby nations.
Vunipola played club rugby in Wales alongside his brother and Union CEO Fe'ao.
He said the respective rugby communities have had a historically close relationship.
"And then luckily now that one Tongan boy, Toby Faletau, is a good ambassador for Tonga who plays for Wales now.
"I think there is a lot of good things for Tonga if we can try and carry on our relationship between two countries in rugby," Vunipola said.
"A lot of Tonga players, they play in Wales now."
Samoa are also scheduled to host Wales on Saturday 24 June.
Photo: Tonga Rugby Union (The Tongan team training at Nuku'alofa's Teufaiva stadium)