This could be true but not for lack of reporting. The deficiency would be in lack of testing since testing isn't mandatory. People that decide to get tested feel some kind of symptom. Those that are asymptomatic will rarely, if ever, volunteerily go get tested.
As most nations adopt strict quarantine measures to protect themselves from the coronavirus, the Nicaraguan government has taken quite the contrarian approach, declaring the pandemic risks overrated and encouraging citizens to go about their everyday lives.