But on Thursday, a coroner ordered the release of the bodies of Margaret Owen, 72, and Andrew Owen, 53 who were found in their home in Ferndale, Pant, on April 21 this year.
Detective Constable Geoff Anslow told senior coroner John Ellery that police have no further need to hold the bodies, which have been kept in "deep storage" since their deaths.
Police had been treating the deaths as an isolated incident in the village but wanted to finalise their conclusions as to what had happened.
A furious Mr Ellery told a pre-inquest hearing that he found the toxicology report delay to be "unacceptable".
"It is taking too long and we are doing all we can to get these tests done and to bring one or both these inquests to a conclusion," he said.
The inquest into Mr Owen has been opened but tests are being awaited to see if one is required for Mrs Owen. If her death is put down to natural causes, Mr Ellery said there would be no need for an inquest on her death.
DC Anslow said: "The investigation into these deaths is ongoing due to waiting for toxicology tests to be carried out on both."
Mr Ellery said: "We are doing all we can to bring forward or take to another test lab. Until we get the toxicology report we can't progress an inquest for Mr Owen. And there may not need to be an inquest for Mrs Owen if her death was due to natural causes."
Mr Ellery authorised the release of the bodies to the family so that a funeral can be held. The hearing was not told why there has been such a delay in getting the results back.
DC Anslow confirmed that he was happy for another test provider to be used, but the inquest heard that this could still take another six to eight weeks for a result to come back. A pathologist would then need to conclude a cause of death.
Mr Ellery decided to adjourn the inquest until January 31, 2022.