Create a filter in PHP to force an image

I would like to use a filter, or some other PHP method to force my own image (based on exterior factors) to a wordpress post when sent to Facebook.

Let’s say I have defined a full path to a PHP constant

define('MY_FP_IMAGE_PATH','https://mydomain.com/images/something.jpg')

This is now the image I wish to use in the facebook post.

I will gladly pay for the pro version, if this can be solved with a filter, or some way without changing any of the plugin codes.

My single post page, for this category already includes the meta:

<meta property='og:image' content='https://mydomain.com/images/something.jpg' />

I was hoping if I set it to “Let Facebook Select” it would use this property automatically, but did not.

Any advice would be appreciated.

https://www.ads-software.com/plugins/add-link-to-facebook/