epos_hardware list_devices throws Bad Parameter errors for port names and interface names

[ahkub]

Hi,
I'm running ROS Noetic on Ubuntu 20.04.6 LTS. I git cloned https://github.com/RIVeR-Lab/epos_hardware.git. Then I fixed hardware.h, as described in "error: ‘scoped_ptr’ in namespace ‘boost’ does not name a template type #7" in the Issues section. Then I ran catkin_make. I did the sourcing "source devel/setup.bash".
"lsusb" shows my FTDI USB-to-COM adapter
"dmesg | grep FTDI" shows the adapter, too
I fixed the USB permission issue, as described here "https://answers.ros.org/question/216315/help-using-epos_hardware/ "
Now: when I run "rosrun epos_hardware list_devices", I see this:

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Listing Devices:
EPOS2
MAXON SERIAL V2
USB
Could not get port names: Bad Parameter
MAXON_RS232
RS232
Skipping RS232
CANopen
Could not get interface names: Bad Parameter
EPOS
MAXON_RS232
RS232
Skipping RS232
CANopen
Could not get interface names: Bad Parameter

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I have spent hours on trying to solve this. Would anyone have a good idea how to fix this issue?
Much appreciated.