On an old question (https://cadabra.science/qa/162/usage-of-vielbein?show=162#q162), the implementation of the property Vielbein was requested. While it was implemented, as well as the property InverseVielbein, the implementation of the algorithm eliminate_vielbein is not yet implemented.
Vielbein
InverseVielbein
eliminate_vielbein
Have merged your initial docs and the actual algorithm now. There's room for improvement of course.