Aware that the kinship of the elements in the question above depends on the research question, I would like to know what is the best approach when investigating a novel phenomenon. Thank you.
One of the key elements of Grounded Theory is that data collection and analysis proceed together, so that as you collect each round of data, you stop and do preliminary analysis that guides the next round of data collection. If you can meet that standard, then I would recommend GT as a method for exploring a novel phenomenon.
The research topic and its questions are the best guide for choosing.
If you are looking for descriptive answers in your research topic and you want to make research conclusions based on those descriptions and you are not looking to present a single procedure, the descriptive phenomenological method is suitable.
In this way, you can advance the research process by using appropriate approaches and intentions.