Is this “pinking up”

I’m adding these pictures as my friends indoor cat Rosie, she got let out by a workman. she went missing for three days before coming home safely. This would about 3 weeks ago. she’s been in touch with the vet and got a quote of £250 for consultation and ultrasound. before she spends that, she would like to see if this actually looks like “pinking up” as she’s not sure what non pregnant cats nipples are meant to look like. thank you so much for your help! 

It's very difficult to tell from a photograph, because the light levels are so variable, which tends to wash the colour out. There are also some variations in the "normal" colour of the nipples, just to make it more complicated! From these images, I'd say this looks suspicious but not diagnostic, at this stage The big question will be whether knowing she's pregnant will make much difference: will your friend want to keep the kittens? If so, then it will be important to know if she really is pregnant. If not, then it might be worth talking to the vet about other options. If she will want to keep the kittens, then it's a question of deciding whether or not the scan will change how she's managed. Another useful test could be to see if she returns to calling again after her escape - if not, again, that suggests that she is pregnant. However, at the end of the day, your friend isn't going to know whether she's actually pregnant, or has a false pregnancy (uncommon in cats but not unknown) without a scan. I really think the best solution is going to be for your friend to have a chat with the vet and decide whether the scan is going to change how she manages Rosie, and if not, whether other approaches make more sense. Hope all goes well!