Testimonial campaign cards - embedded text question

Hello there,

We recently completed an audit of our website for images and alt text.

One of the things we are trying to avoid going forward (unless it's necessary), is having images where the text in embedded. We can do this by posting the text next to an image on our website and make it look attractive still. However, in the case where we are using a twitter card on social media that has a student testimonial of about 60 odd words (see example attached), does anyone know if the Twitter image description is even a suitable alternative for creating some social media "alt text": https://help.twitter.com/en/using-twitter/picture-descriptions. And have we failed accessibility by following a certain practice on the web, but not on Twitter?

Sorry it's slightly on a tangent if related but would just appreciate your thoughts on this as both web and social will often work hand-in-hand on this.

Best
Louise

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