Original YR? CloakStop=yes doesn't even work in YR without Ares.
Confirmed happening for vehicles in 16.15.1117.
Also a note: assuming AI control doesn't immediately trigger this behavior for pre-built vehicles, only after the AI adds them into a taskforce. Vehicles built by the AI suffer from it from the start.
Are you sure it's not something else? My AI has no problems with my CloakStop=yes infantry.