You know, I kinda find it hilarious to see how the thread's moving in circles.
Well, here is a full recap. And a plan.
We got:
-A liegelord which doesn't like us.
-Not established (yet)
-Married to the Count's lawfull daughter
-The Count's bastard
-Unknown Pretender
-Unlawfull
-Probably Replaceable.
The Plan:
-Weaken the Count's position
-Rumours about the last Count's death
-Strengthen the Bastard's position
-Introduce him to other Nobles (not nessecerially as the Count, but at least as someone of importance)
-For that he will need to leave Feroshire*
-Other things I forgot
Worst case scenarios:
-Attack on Feroshire
-Chance of aid from fellow lieges, maybe under the banner of the Count's bastard
-Attack on Percival
-Legitimates us to attack the Count, together with some of the other lieges, and maybe even Ducal support. In any case, will probably result in the Count being removed
So yeah, I don't see what extra value gaving the Count's bastard with us gives. Ok, he's safer here, but remember that we're not doing this for his safety/ his good, we're doing this to remove the New Count from his position. If the lad dies in the attempt, bad luck, but not the end of the world. The only benefit is that it would allow the complot to remain hidden longer (reduced chance of the bastard pretending to much), but in the meantime little progress is made. The longer the Count remains throned, the better his position becomes.
*And as per Gerv's suggestion, get to Percival's house. Besides, if we keep him under our thumb, people will start to consider him our creature, which might turn out badly for us. We want to let them thing we support the bastard as lawfull heir, because the new "Count" murdered the old, not because we don't like him.