So you are looking for the amount of concurrent users from License perspective when allowing anonymous users for your deeplink? I would say: yes, they count as Concurrent Anonymous User Sessions when a Mendix Session is created. If you just link to an image, then this is not the case.
The red line in the seconds graph on the trend page will be influenced:
And in the license part on the Environment page you can view your limits due to your license:
I'm not sure what you exactly are looking for, so I will approach it from the perspective of amount of concurrent users. Then the answer is no: if the user has already a Mendix session, that is reused on clicking a deeplink. This means that single user has still one session and therefore counts just one concurrent user.
Does that answer your question?
For reference, this is a snapshot of Deeplink version 5.2.0, which tries to reuse the session on line 153 (except when logging in):
Reading your usecase it seems you might want to even skip the deeplink all together. You want to enable anonymous users and use the URL property of normal pages to redirect ppl to the right page. Make sure this single page is available for your anonymous users and you should be good to go. Unless you require more then 1 page parameter to retrieve data for your anonymous users. That is currently only solvable with the deeplink module.
We want to show a mendix mobile page from a different application. These users will not have mendix user names they will not have access to our application just one landing page and one or two more to add info. When these users click on the mendix url from the other application will it be seen as a concurrent user? they wont be logged in anywhere in the system as they are not mendix users.
Ive done some tests and it looks like the deeplink does not get picked up as a user. Can mendix confirm this please as hundreds of people are going to use this deeplink.