Triggering a change or input event in a non-input ReactJS field

Question

I'm trying to update the value of a <figcaption> field with the textbox role using Google Console. I've been able to update form fields using the solutions described in What is the best way to trigger change or input event in react js , but this field just won't update. I'm able to set the text content of the element using element.textContent = "mynewvalue", but that doesn't update the value the form value. I also tried looking through element.__reactProps$... and element.__reactFiber$... for events and using those to trigger updates, but no luck. The field works when I type in a value, so there must be a way to do this. What else can I try?