Evans, a member of the worldwide development select committee which will question Goldring and chair of trustees Caroline Thompson today (February 20), told talkRADIO he and his colleagues want to get to the core of the scandal, and will leave no stone unturned.
"We really want people to come forward", he added.
Oxfam said today it was investigating 26 new cases of sexual misconduct which had been reported since a scandal broke earlier this month over its handling of a 2011 case in Haiti.
Made public earlier in the day, Oxfam's 2011 report into the behaviour of aid workers sent to Haiti following a devastating natural disaster revealed that a former top official admitted to paying for sex and that three staff physically threatened a witness. "We are also meeting with the government of Haiti to apologize for our mistakes and discuss what more we can do, including for the women affected by these events".
Simon Ticehurst, regional director for Latin America and Margalida Massot, Executive Affiliate Unit head, met with Haiti's Minister of Planning and External Co-operation on Monday to present a formal apology.
The global charity, which has offices around the world, has already been severely damaged by the allegations which were first reported by the Times of London in early February.
While the inquiry was still underway, the line manager of one of the suspects leaked a report to another member of staff.
Prime Minister Theresa May described the disclosures in the report as "absolutely horrific" and warned standards had fallen "far below" those expect of the charities and the NGOs that work with the Government.
'Black Panther' star pays for over 300 SC kids to see movie
As for the movie, it not only features a black main actor, but is set in Africa with a largely black cast. Black Panther was released last Thursday in the United States and premiered at the weekend in Zimbabwe.
The charity's embattled Chief Executive, Mark Goldring, apologized to lawmakers for its conduct in the aftermath of the 2010 Haiti natural disaster.
It comes as a Scottish mine-clearing charity made famous by Princess Diana has suspended a member of staff over a sexual assault allegation.
According to a 2011 internal probe by Oxfam, released earlier on Monday, seven employees left the organisation as a result of the investigation.
It also said that the director of operations in the country had admitted paying for sex, but was offered a "phased and dignified exit" by means of resignation if he cooperated with the investigation.
Oxfam has denied trying to cover up the allegations but admitted it could have been more open at the time, saying it was publishing the report "in recognition of the breach of trust that has been caused".
A spokesman for the Halo Trust said: "In Myanmar, a junior Burmese member of staff was suspended in January this year and is now being investigated following an allegation of sexual assault".
Recent news reports have criticized the charity for allowing some of those involved in the Haiti allegations to move on to jobs with other aid agencies, and the report highlighted this as area of concern.
Oxfam denies covering up the findings of its internal inquiry.