I have also the same problem!
I have also tried to heal those devices but it keeps the same route and 4 devices are still unreachable and do not work 
I also use homee and an Raspberry Pi with Razberry Z-Wave-Modul -> If I include the same Z-Wave devices at the same position both (homee and Raspi -> same position like homey) work without any problems.
Has anyone an idea to expand the z-wave range without installation of external antennas?
