One man solution
Your GCPs are already measured by GNSS. For GPS denied areas you need a one-man fully-operational robotic total station. Autamation performance, extended reflertorless measurement capability, STReaM360 and reflectorless measurable distances up to 1000m.
An ultimate answer for all survey engineering companies who are looking for an alternative to green, blue and grey instruments but have to achieve 1“ accuracy.