Dynamic text still editable, need to be locked

I have a single cf7 form in use on an artist gallery, on each artist’s page – it “grabs” the name of the artist – [dynamichidden title “CF7_get_post_var key=’title'”]

and places it into a dynamictext I’m using as a “subject” field – [dynamictext title “CF7_get_post_var key=’title'”]

It works, yay, and its populating with the artist name in the contact form — BUT – it is still editable, so a user could conceivably change it (Not desired)

Tried to add readonly, but that makes the field disappear, tried to set it to disabled, in the hopes it would be so, but that too, makes the field, disappear.

Is there a way to still see the captured data but not be able to edit it??