Use custom shortcodes as Contact Form 7 checkbox/radio-button value

Hi, I am creating a form that allows users to register for different events.
For the events I created a Custom Post Type with CPT UI and added Custom Fields to it with ACF. Each Custom Post Type = Event hast up to 6 Custom Fields of which each only contains a date for the event on plain text.
Everywhere else on my side I use the shortcodes of the Custom Fields to display the event dates. This allows the person who maintains the page to only change the event dates in the Custom Post Type and it gets updated everywhere (pretty simple solution but it works for my small page).
Now I want the registration form to display the event dates in a way that makes it possible to select the date that the user wants to register for.
As far as I figured out using several different plugins (e.g. shortcode enabler, dynamic text extension) I cannot integrate a custom shortcode (of my custom field) into the cf7 form field tags.
But I would really want to find a solution for this – is there any way I can pull my custom fields data as values for my form fields? Grateful for any idea!