How to get Google Images to pick up image titles from Hugo website when using Shortcodes?

Question

I have a Hugo v0.74.3 home run website and it has some pictures on it.

I declare these pictures in the markdown as shortcodes, i.e.

{{<figure src="./media/trng-dilemma.png"
title="The TRNG dilemma."
alt="The TRNG dilemma: Are any true random number generators really random given the stakes and circumstances?" >}}

which Hugo converts to the following HTML:-

 <figure>
    <a href="http://192.168.1.70:1313/media/trng-dilemma.png" data-featherlight="image"><img src="./media/trng-dilemma.png" alt="The TRNG dilemma: Are any true random number generators really random given the stakes and circumstances?"></a>

    <figcaption>
            <h4>The TRNG dilemma.</h4>
    </figcaption>
 </figure>

And it all renders correctly :-) But you see that the title text is now a figcaption. So the problem: Google Images displays that image as:-

It has not picked up the figcaption at all. Despite Google stating that they suck up figcaptions. Neither the alt text. It's actually displaying the website main title:part of the meta description and home URL. And Google does that for all of my images anywhere on the site :-(

This seems to be the intended behaviour, but it doesn't seem right to me as part of the site's informatics gets lost.

Q: How can I get my image title to be displayed by Google Images?