It seems this is not an issue localized to the Vantage drivers nor my code.
Copy and pasting the code from the PyINDI Tutorial into a Python script and running it results in the following output.

INDI::BaseClient::connectServer: creating new connection...
Traceback (most recent call last):
  File "", line 82, in <module>
    telescope_on_coord_set[0].s=PyIndi.ISS_ON  # TRACK
TypeError: 'ISwitchPropertyview' object does not support indexing

After dissecting the attributes of various I*type*Propertyview objects I have yet to find one that allows me to access the output of the sensors associated with any equipment.
The readings are displayed within the INDI control panel in Ekos which leads me to believe the issue lays in PyINDI. Was there a change in methodology in PyINDI or is this a bug?

I am using version 0.2.7 of the pyindi-client.

If this isn't the correct forum to be using for this issue, a nudge in the right direction would be appreciated.