objective secured outside of a transport?

If I run the CAD and a troop unit embarks on a transport vehicle which was selected as a transport for an elites squad, and these troops inside their elites transport boost onto an objective, will the objective secured rule be applied from the troops inside the transport?

And does it work the other way around? Elites infantry embarking on troops selected transport that is within an objective? Will the objective be held by the transport, thus objective secured?

IIRC you have to specify which unit is holding the objective, so you could declare it to be the obsec unit.

I'll defer to the Count though, who will no doubt be able to tell us!

I've had a glance through the rules, and they don't prohibit units inside transports from counting as scoring units (unless its a Zooming Flyer they're embarked upon).
As such they can hold the objective, contest the Objective, and count as using the Objectvie Secured special rule.

Further, the rules say that "You control an Objective Marke rif there is at least one model from one of your scoring units blah blah blah within 3" of it."
It doesn't preclude an Objective being held by multiple units.
What itdoes preclude is one unit holding more than one Objective Marker, in which case you must declare which marker the unit is holding.

If your ObjSec unit is within range to control the objective (measuring from the hull of the transport) then it doesn't matter if they're embarked on a non-ObjSec transport, they can still control the objective.

Similarly, if an ObjSec transport is within range of an objective then it doesn't matter that a non-ObjSec unit is embarked on it. The transport will still control the objective.

Thanks count, that was also my interpretation and I am glad that you confirm as you are obviously the rules guru here

That actually has an important implication to my army: I will swap troop transports with elites/hq transports during the game in order to have one additional unit gaining obsec (court getting in originally by kabalite warriors selected raider + kabalite warriors getting in originally by court selected raider)