I need to know which of these two research strategy fits a work that aims to firstly investigate the factors influencing startup incubation process in a certain case ( one tech, incubation center) and next to design a model for that.
I don't think these are contradictory research strategies, since the emphasis in phenomenology is on lived experience in some specific set of circumstances, and those specific circumstances can also define the basis for a case study. In other words, you can do a case study of something using a phenomenological approach.
I have to wonder if you have been overly influenced by Creswell's book, "Qualitative Inquiry and Research Design: Choosing Among Five Approaches," which could easily be interpreted as implying that case study research and phenomenology are somehow mutually exclusive.
Having said that, I personally think that your goal to "design a model" is probably a better fit with a case study approach than phenomenology, simply because the more mechanistic aspects of model building don't correspond to the typical reasons for doing phenomenology
Yes, Creswell makes the two methods mutually exclusive. Though his book makes some overlapping methods distinct from each other, his book is very good in describing methods of qualitative research for beginners to make initial choices as to which method to be used for what type of researches.