If she owns it, they have nothing to say about where and how she displays it. It is hers.
If they don’t like it there, they can offer to buy it back.
I am sure Ivana would charge them a reasonable price.
Yeah, let them buy the pictures back from her. They are HER property, and she can display them as she sees fit.
An added bonus - if they come up with some significant money to buy them, then they go on record as having some money. If they happen to also be collecting government benefits (food stamps, welfare, section 8, etc.), then they are setting themselves up for an investigation and potential charges.