I've just been searching Irish Civil Registration records, and discovered on an 1871 page, four deaths from this asylum from 1864 and 1865 that were not officially registered until 7 feb 1871
Honora HEWSON, widow, died 18 dec 1864 at Magdalen Asylum, Limerick, aged 56
Mary Anne GODFREY, spinster, died 7 dec 1864 at Magdalen Asylum, Limerick, aged 44
Mary ROBINSON, spinster, died 10 apr 1865 at Magdalen Asylum, Limerick, aged 26
Anne SYNNOT, spinster, died 28 jun 1865 at Magdalen Asylum, Limerick, aged 28
As these were the last four records on a page, there may be other late recorded deaths from the same asylum on the following page or pages. That means that it may be worth looking for names of interest well beyond the date you know the person to have died.
