@MJ154 , I am sorry for your loss.
On the 3520, you can either file it with a note explaining that it was an error and mail it to the address shown on the form. TurboTax does not support this form., if the valuation of the asset was above US$100,000. You can also ignore this and take the risk that IRS does not check on this ( this is because when you recognize the disposition of the asset on your 2023 filing , you will need to answer how you acquired the foreign asset). Either way it is risk but I like the first option better.
A point to note is the condition under which your father gifted you the asset --- if there was stipulation that you cannot do certain things ( like sell ) till your father has passed -- in the US this Life Estate -- then the gift is constrained and therefore not quite a gift till the passing of the donor. In such a case I would argue that the basis should be the FMV at the time of passing ( whether he used it or not ).
If that is the case you should perhaps consulta tax attorney to be able to homologate Polish and US laws.
If not , then my earlier statements stand.
Is there more I can do for you ?
BTW -- if this has answered your query, please accept the answer so the thread closes.
