I can access the screws underneath the toilet but they are placed horizontally like as if they are screws holding the toilet bowl to the wall instead of downward facing screws holding a toilet seat to the bowl. Does this look right to anyone? How best to proceed? Any advice/reassurance welcome Dash
Those horizontal studs and nuts / washers do hold the toilet to the wall.
The seat fixings are too far back to have an easily accessible fixing from below.
You might find that you will have to take the toilet off the wall as the seat hinges are fixed through the porcelain and usually just start rotating once they are loose, at least that has been my experience.
Look at this video starting at about 11 min 30 s. Grohe wall mounted toilet
EDIT I see a screw exposed under the swing away cover in the picture posted. I would assume that unscrewing it would release the fitting holding the seat.
It might be wise to consult the landlord even before a seemingly simple change of a toilet seat. Maybe his staff know how to do this and would do it for you.
EDIT2 Have you looked or felt under the bowl to see if seat bolts are visible? See What kind of tool do I need to access this bolt?
Do NOT touch the horizontal bolts/nuts.
It looks like the Duravit starck 3 wall mtb wc. You can view the different versions of the Starck 3 toilets with specs to clearly identify the model you have. At www.duravit.us. To determine which you have ,Measure from the wall forward along the top.
It looks like you’ll need their most common toilet seat is a Duravit 0063390000. It’s the slow close version.
Keep in mind that there are 3-4 models of the starck 3 bowl, and each gets a different seat/cover, in slow close and non slow close.
Keep in mind that Duravit is a premium-luxury fixture brand which is not really geared towards “diy” customers.