Thanks for the pictures - quite a challenge!
I've spent an hour or so on the shots this morning. It's brought up a few questions and challenges!
Who should be in the shot - 5+dog, or just the 5.
What 'look' are you going for? The clean white background, studio shot? or do you want the texture in the background?
Because of the dappled nature of the lighting (which I presume was through trees?) I'm not sure you'll be able to get the 'clean' 'uniform' studio look.
The lighting would look right against a backdrop of trees etc, but it looks 'odd' against the white sheet, perhaps because you expect more uniform lighting for shots against white.
I also don't think a clean white look will work because of the shirts of the two on the left.
There's also quite a lot of movement between the shots which is making replacing faces etc with less harshly lit ones a little challenging.
This is the result of around an hours worth of messing.
It's from a single shot, I've just masked out the background, a bit of dodging and burning on the faces to give a more consistent look to the light, and then applied a Fuji Superia 400 film preset to the image in lightroom to slightly mute the colours and add a small amount of grain to the image as a whole to lessen the effect a little of the white background. I don't think it works, but it's the best I came up with. I tried a B&W conversion too, but there's too much structure in the image to make it work well (for me at least).
View attachment 4050
Google Drive links to...
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JPG (about 3Mb)
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PSD file, with layers / masking (about 100Mb)