I'm sure the film's budget could have afforded a consultant. However, if you watch the movie, you may notice that there was no need to show ProtonMail at all. It was a close-up, over-the-shoulder shot of the culprit using a phone to send an email. The whole shot lasted ~2 seconds, with narration. They could have simply chosen a front-facing shot of the culprit using a computer or phone to achieve the same affect.
In any case, there are still plently of TV series and movies that put less effort into a 5 minute 'hacker' scene than this movie did into a 2 second shot. They get my kudos.