Hi Tom: It's nice to hear from you again. The Tulla Workhouse records do not survive, but the civil registration would give information about any births, marriages or deaths that took place there.
You should be aware that after the Famine, many of the Workhouses were used as community hospitals, so just because your ancestor died there, does not mean that he was put into the workhouse due to distressed circumstances. A number of older people and those who were very sickly were brought there as there were doctors and nursing staff.
Let me know if you have any more questions. I know that you have my personal email address from previous correspondence. If you wish, you can also contact me at: tulla@irelandxo.com.
All the best,
Jane