So after some tests I can say that the fix didn’t work for me.
With the fixed variable, now I have the IPs in the error message but it says again,
check_icmp: Failed to resolve 8.8.8.8 9.9.9.9: Name or service not known
The same with IPv6
check_icmp: Failed to resolve 2001:4860:4860::8888 2620:fe::fe: Name or service not known