Is it permissible for me to pray at my workplace due to my inability to go to the mosque except for Fajr, Maghrib, and 'Isha, knowing that I work in security in Abu Dhabi?

If work conditions necessitate staying on guard duty, then there is no harm in not going to the mosque, and the person should pray in their workplace. Fear for one's livelihood or for money entrusted to one's care is an excuse for missing congregational prayer, along with the effort to pray in congregation with another person.