Honestly, I cannot see how an agent can operate properly if I (as an employer) can't find out how to CONTACT them.
The only telephone number is voicemail. If I am a CD I want to be able to
talk to an agent. If I want to book a model, I want to know their availability - I don't want to have to fill in a form and wait for a response. Why do I have to write to them? Where
exactly are their offices? Why can't I visit them? Where does the photo shoot take place? Where does the interview take place? I would suggest finding that out!
I would be very dubious about this. I expect they will try to sell you photographs.
If you want to find acting work, join an acting agency (Assets isn't one). If you want to be a model - go for a meeting with a modelling agency (
you don't need a photo shoot for this). If you want to join a commercials agency - send your own photo and CV and see whether they will accept you.
Photoshoots needed for representation are a
big red flag. Be very wary!
Also, do some internet research into this company - there are certainly enough people out there suggesting that this is a photoshoot scam (i.e. free test shoot and then offering to sell you the photographs - for lots of lovely money).
And welcome to NAPM by the way! It's always interesting to see what prompts someone to post on the forum.

Do report back, won't you?