Margaret could have averted 2 disasters in the same episode

In 'We Have Put Her Living in the Tomb' (s02e02), Mrs Warboys is given a bottle of hair tonic for her husband by Margaret, unaware that it actually contains Victor's urine sample.
Almost as soon as Mrs Warboys leaves Margaret learns the truth, but rather than go after her, or attempting to call her house, she appears to simply disregard it. We later find out that Mr Warboys used the urine on his hair.

Then later, after Victor accidentally cremates the tortoise and informs the owner, Margaret buys a replacement and takes it to the owner in a box, unaware that the owner had already been informed that it died.
Later that evening at the car park, Margaret learns from Victor that the owner knew the tortoise was dead, and she even seems to realise that they will likely bury the new tortoise alive (which is exactly what happens in the following scene).
The burial scene occurs in daylight, and so probably happened before the preceding car park scene, however there was probably still time to dig it up and at least check if it was still alive. As it was in a box it probably would have lived for a few hours.
Admittedly this is where the episode ends, and I suppose you could argue that they did go back to the owner and tell then to dig up the tortoise, it just isn't shown - but given the often tragic strands this show weaves I get the impression that the second tortoise died too. And again Margaret could have averted it, but she chose not to.