@Jossi1973 I can share my experience with both units.
As Tedtolboom wrote above, you must first exclude those units before an attempt to include them. If for any reason during the inclusion process things get stuck, then go again through the exclusion process before attempting another inclusion of that particular unit.
FGS-212, for some reason I had to factory reset this one as it did never manage to exclude using the triple click of the B button. The manual has a very ambiguous translation (at least the English part) when explains how to factory reset. In essence you must hold down the B button and then apply power. Keep holding the button for like 4-5 seconds after power applied. Then disconnect the power. Put Homey into inclusion (add new device etc…) then apply power to the FGS-212. No need to triple click the B button, soon as after you apply power Homey will find the FGS-212. Basically this guy if factory reset and power on, it goes straight on into autoinclusion process. From the moment you apply power to it you have 30 seconds to get Homey into inclusion so that’s why I said first get Homey to look for the device then apply power to FGS-212.
As per @TedTolboom , post Homey does not support network wide inclusion so it is a must that you either bring the z-wave device close to Homey or viceversa.
FGMS-001 exclude first. It is only done when you get the message that it has been excluded. Bring this one close to Homey and triple click fast the B button when prompted.
Then include the unit and my suggestion is to select Z-Wave and not actually the Fibaro app and the device itself. In this way you are sure that Homey will find the right unit as FGMS-001 has a couple of options.
Initially I had similar issues like yourself but the above worked well for me, hope this helps you.