When it's placed behind a paywall, I'd say using a photo on Medium constitutes commercial use, but there are often allowances for editorial use among organisations who want the press to be able to use their images.

You say the images come from a press room. That suggests they are intended for editorial use. A lot of editorial is behind a paywall these days. I'd say you should check with them and they'd probably reply favourably.

If your article is raising awareness of their product, I would expect them to be pleased to allow you to use their photos.

Perhaps drop them a quick email to explain that you've written a positive article about their products, it's behind a paywall, but non-members get three free reads. Do they have any objection to you using their pics.

Is it the same company repeatedly? Because if so, a positive response would clear you to use all their press room pics. Then hang onto any permission emails, in case it crops up later.

I wouldn't worry about a takedown notice. If you get a takedown notice, you take it down. It's the possibility of fines I'm more concerned about.