Parents who contacted the Weekend Herald this week were scathing of the investment decision.
"Horrendous, how could this happen? We'd donated money to Dio - to see them waste it like that is pretty disappointing," one said.
"Clearly there were not 'robust governance and investment protocols in place', otherwise they would not have wasted so much money fundraised through the efforts of the community," said another.
The concerned parents did not wish to be named to avoid repercussions from school management for their daughters.
In an unsigned statement sent by a public relations practitioner in response to Weekend Herald questions about concerns parents had about speaking out publicly, Diocesan said: "Any person in the school community who has questions in regards to the foundation are encouraged to contact the trustees directly, as they believe this is the appropriate forum for any discussion."
The affair triggered a bout of infighting within Diocesan, with board of trustees chairman Andrew Peterson yesterday sending an email to parents saying the Penrich investment began in 2016 "on the recommendation of AMA Capital and with the approval of the foundation's investment committee".
The email notes: "At the time, Angela Anderson was chair of the Heritage Foundation and principal of AMA."
The Heritage Foundation's current investment committee is comprised of finance industry heavyweights Anderson, David Ballentyne, David Gibson, Geoff Lawrence and Peter Green.
None of the committee, with the exception of Anderson, wished to comment further about the Penrich investment when contacted by the Weekend Herald this week.
Anderson said her work with Dio was pro bono and AMA charged no management fee to the Heritage Foundation and she also had invested her own personal funds with Penrich.
Both Anderson and Peterson cited a review by investment consultants MyFidiciary commissioned by the Heritage Foundation in the wake of the impairment that concluded Penrich appeared to be a "well-executed fraud" that was "not possible (or extremely unlikely) to be picked up via the standard reporting and disclosures of the firm".
Peterson's email to parents on Friday morning included a barb at media scrutiny of their finances: "It is important that you are aware of the facts and not just the information the media will choose to use."