How? I mean I get it, leaving 50 people on the hook is terrible and all but this is not the PM's call it would be the minister in charge who at the time thought Ukraine would fold in 3 days.
$1:
The decision to leave without informing local staff members or providing for their safety was based on a Canadian policy articulated in a Harper government memorandum in 2014. According to one of the diplomats who spoke to The Globe, the document said there should be no duty of care for locally engaged staff when an embassy is abandoned. Another of the diplomatic sources said the memo was drawn up as justification for Canada’s 2012 decision to close its embassy in Iran without evacuating local staff there.