This paper puts metal layers in between the PDMS and PVDF for better adhesion and electrode fabrication:
https://www.mdpi.com/2076-3417/8/2/213/pdf
I think there is going to be bad adhesion between PDMS and PVDF until you do something to compatibilize the interface..
From my background, I would probably take an approach of grabbing a strong spot cure lamp and irradiating the PVDF/PDMS with deep UV irradiation to crosslink a thin layer of PVDF to the PDMS surface. Then, rinse away unbound PVDF with solvent, and then apply the new layer of PVDF. Hopefully enough crosslinked PVDF will be photobound to the PDMS to act as an anchoring network to promote better adhesion here.