Capital gains on sale of property where spouse has recently died

I am helping a friend complete a tax return. In the 2022/3 tax year, he sold a property in Barbados. Let’s say the sale price after allowable expenses was £250,000 and the purchase price £150,000, meaning a gain of £100,000. However he co-owned the property with his wife and she died two months before the sale completed. I believe both names were on the ownership documents. He tells me he has been advised that he only needs to pay capital gains on 50% of the gain. He further says that capital gains falls away on death and that the profit from the remainder of the property transfers to him as part of his wife’s estate. Is that correct? If so, how should I account for it on the tax form? It’s not at all obvious how to do that. Also I note that Barbados has a tax agreement with the UK. I think some taxes on sale were paid on sale. Can these be reclaimed or offset against UK taxes?

Hi
He would be the owner of 100% of the property upon the death of his spouse and as such would be liable for capital gains on the full disposal.
He will take his share of cost price at the time purchased and then have a value of the house at the time of death to then take the other 50% value of cost price to then claim this as purchase price.
If tax paid abroad, he can claim foreign tax credit relief to reduce any UK capital gain.