However, if the Netskope client is active, and the user is on the company's network (without being on the vpn) the site is accessible.

It also becomes accessible by disabling the Netskope client, and leaving and rejoining the VPN after disabling.

We have already forced traffic through NPA

Does anyone have any idea what might be going on?

Encountered a file package download error

nsUtil Failed to auto detect proxy or download PAC file, error 12180