Divorced families when one parent is from another country

[Mummy195]

My neighbour is struggling with finding coherent information on this, and so am I, so I said I'll check on here.

Her XH lives in one of the countries that mean he has to isolate when he gets here. He wants to come over the half term to visit the kids and insist that he must stay at her house as he is not allowed to have visitors if he goes to an AirBnB. What does not make sense is that he is allowed to visit family and and stay at their house, but he is not allowed to have them unless he has isolated for the 2 weeks - time he cannot really take off from work anyway. None of this makes sense to me as why should the venue be the issue here?

She does not want him at her house and feels a bit like she will be bullied to leave and stay at a BnB or something. She does not want to come across like she is preventing him from seeing his kids either.

Anyone with this experience or knowledge?

Scroll down to the bit "Within your accommodation". I assume he wants to stay at her house so that he can see the kids while "isolating". However, the whole point of self isolating is to keep yourself away from other people so even if he stays there he should stay as far away from others in the house as much as possible i.e. stay in his bedroom, have food delivered to the door and use a separate bathroom if possible.
www.gov.uk/government/publications/coronavirus-covid-19-how-to-self-isolate-when-you-travel-to-the-uk/coronavirus-covid-19-how-to-self-isolate-when-you-travel-to-the-uk