If you contact the GRO you can request any certificate for which you can provide the details
https://www.welfare.ie/en/Pages/Apply-for-Certificates.aspxIf you apply on line it is far more expensive than posting a query but they will email a reply if your request it
Any death deemed undetermined in cause, unusual in manner, not under a doctor's care, etc. would most likely have had an inquest and this could delay the issuing of a death certificate so it may not necessarily be in the same year. The Coroner's comments are often quoted as the cause of death.
The first entry on this page is a distant cousin of mine that died in an accident;
LINKJust as an example of how the coroner may be referred to
You can see it states the date the inquest was held which can be useful for further searching