Is it permissible to work for a company that performs journalistic and television documentation of materials that may include forbidden things, knowing that the nature of my work is a telecommunications engineer responsible for network infrastructure, systems, and devices? And is it permissible to remain in this job until another job is found?

If a company's activities are mixed, between the permissible (halal) and the impermissible (haram), then the ruling depends on what predominates. If the permissible predominates, there is no harm in continuing to work, though it is preferable to leave. It is forbidden for you to carry out any work related to something impermissible, even if it leads to leaving your job at the company. It is not permissible to continue working there except out of necessity, and only to the extent of that necessity, while searching for another permissible job.