You may be correct, but the CDC does have a category for deaths where intent is undetermined.

The problem is how to unpack any “insurance suicides.” Unlike its non-fatal injury reports, which are estimates based on a sampling of hospitals, the CDC’s fatal injury reports are based on death certificates from coroners and justices of the peace as reported to state vital statistics agencies. So I am not sure how any researcher could obtain enough information to determine the actual cause of death, whether it is an actual accident or a suicide.

Given the low number of accidental deaths (486 in 2017), it’s not too difficult to believe that there are actually that many people stupid enough to leave guns where kids could get them; fail to check if their gun is actually empty or keep their finger off the trigger.