My opinion to your scenario is as follow:
It is definitively aerial work and not commercial air transport in accordance with EU OPS1, since the intended flight(s) is
- Not open for public;
- Not transport of persons, cargo or mail from A to B or A to A (for the purpose of being transported); and
- The customer has influence on the date and time of flight, as well as on the routing and altitudes to be flown.
[CAP393/259(1), Section 1 Part 33 Page 21]
Therefore, no EU OPS1 AOC is required.
[CAP393/261, Section 1 Part 34 Page 1]
In most countries, Aerial Work needs a permission to be performed commercially, but this permission is based on national law and therefore must be issued by the national authority.
Therefore, CA (the company who owns the aircraft) needs to have a permission to perform areal work commercially.
CA may contract a photographer or the Photography Company for such missions, if they do not have own qualified personnel. They also should have a description in their manuals how such contractors are selected and trained for this kind of operation.
The same is applicable for the pilot. CA may contract, e.g. on a one-time- or freelance basis, a pilot for certain operations. They also should have a description in their manuals how such pilots are selected and trained for this kind of operation.