This is my first Post in the Forum and english is not my native Language, so don't be to hard if i fail with the Tool Names ;)
I made a Screenshot and spent some time to give it a try - and i hope it is ok for you?! The outside Area was mostly cleaned with the Inpainting Brush. I am trying to restore the People with the Clone Stamp Tool and a little bit of the Smudge Tool. There may be more professional ways to fix this, but i think it will do it pretty well. At first i tried to mask out the Light Reflexes(?) that is on top of the picture and correct it with Brightness and Contrast, but i failed hard ;)
I'm also a completely Newbie in Affinity Photo and Retouching so i took me about 3 hours to get only there, but i won't give up. It's a good Exercise.
Greetings from Germany and Marry Christmas to everyone,
Ben.
http://www.bilder-upload.eu/show.php?file=68af08-1450910167.jpg