What is the legitimacy of fixing the time of the Iqamah and delaying the prayer until the end of its permissible time when there is no impediment other than waiting for employees? Is it permissible for me to leave the company's congregation and perform the prayer alone at its proper time, or to pray in a small congregation of one or two people at the prayer's time, without delaying it?

There is no harm in delaying the Dhuhr and Asr prayers for about an hour after the Adhan (definition), because the time for Dhuhr extends until the entry of the Asr time, and the preferred time for Asr extends until the sun yellows, and the time of necessity until sunset. Delaying the prayer by an hour does not take it out of its preferred time. It is best to perform the prayer early, but if the delay is suitable for the employees to gather, there is no harm. You may pray individually at the beginning of the time, but it is better to wait to perform it in congregation.