As far as I know.  This is not being maintained.  I integrated Forescout with Infoblox in April 2023 and ended up with an Infoblox Tech Support case open for a month.  In the end, I determined on my own before support could figure the issue out, that the documentaion was missing a critical step.

The step that was missing in the documentation was to add the Extensible Attributes to either a individual DHCP Subnet or to the default network view under Administration/Network Views/ default

What led me to discover the missing step in the documentation was watching a Youtube video: y o u t u b e .c o m /watch?v=pnnm17F-D-A&t=1s  titled "Infoblox DDi integration with ForeScout CounterACT"  at the 3:50 mark in the video, it shows the need to add the EA's to the network view.  Hope this helps.