Open URL on Windows and a 64-bit Mac - excel

Question

The following code opens a URL on Windows machines (Excel 2016, 2013, 2010).
I'm trying to make it usable on a 64-bit Mac (Excel for Mac v. 16.22, Office 365 install) as well.
I have tried a number of iterations for finding the Mac library "libc.dylib", and usually get the "Runtime Error '53'. File not found 'libc.dylib'" error. Once I got the error "Runtime Error '453'. File not found '/usr/lib/libc.dylib'".
Here's the code that produced the 453 error:
Option Explicit
Enum W32_Window_State
Show_Normal = 1
Show_Minimized = 2
Show_Maximized = 3
Show_Min_No_Active = 7
Show_Default = 10
End Enum
#If Mac Then
#If VBA7 Then
Private Declare PtrSafe Function system Lib "/usr/lib/libc.dylib" (ByVal command As String) As LongPtr
#Else
Private Declare Function system Lib "/usr/lib/libc.dylib" (ByVal command As String) As Long
#End If
#Else
#If VBA7 Then
Private Declare PtrSafe Function ShellExecute Lib "shell32.dll" _
Alias "ShellExecuteA" (ByVal hwnd As LongPtr, _
ByVal lpOperation As String, ByVal lpFile As String, _
ByVal lpParameters As String, ByVal lpDirectory As String, _
ByVal nShowCmd As Long) As LongPtr
#Else
Private Declare Function ShellExecute Lib "shell32.dll" _
Alias "ShellExecuteA" (ByVal hwnd As Long, _
ByVal lpOperation As String, ByVal lpFile As String, _
ByVal lpParameters As String, ByVal lpDirectory As String, _
ByVal nShowCmd As Long) As Long
#End If
#End If
Public Function OpenURL(URL As String, WindowState As W32_Window_State) As Boolean
'Opens passed URL with default application, or Error Code (<32) upon error
#If VBA7 Then
Dim lngHWnd As LongPtr
Dim lngReturn As LongPtr
#Else
Dim lngHWnd As Long
Dim lngReturn As Long
#End If
#If Mac Then
lngReturn = system("open -a Safari --args " & URL)
#Else
lngReturn = ShellExecute(lngHWnd, "open", URL, vbNullString, _
vbNullString, WindowState)
#End If
OpenURL = (lngReturn > 32) ' With Mac, this may return a dummy variable, but we're going to do it anyways.
End Function
In addition to the code here, I have tried using colons in the file path in place of the slashes. That gave me an error of '53, file not found' as well.