Hi
Firstly, Elsa isn't a silkie. She looks to be more like a sultan.
HeiHei appears to be a cockerel but I'm not sure how good his polish breeding is... I'm no expert on polish or sultans for that matter but I can say quite confidently that Elsa is not a silkie.
What other breed of cockerel(s) do you have? ....it is not clear from your previous posts unless I am missing something.
In the second photo, HeiHei looks to be sick.... it might just be the way he is standing.
Have you been careful about quarantining the new arrivals? Chickens can harbour many illnesses and viruses whilst appearing relatively healthy and it is so easy to bring a nasty disease into your flock by introducing new chickens and very difficult, if not impossible to get rid of some of them (I speak from experience here!!)
Are Elsa and HeiHei your only crested birds? Elsa might get over mated if she is kept with HeiHei and no other females. You would have to try it and see. She might do fine in with other hens but I would be apprehensive for her if she was in with a large fowl cockerel as well. You also need to be very careful about introducing new birds to a flock of hens even after quarantine, as sometimes the pecking order can be brutal and crested birds have vaulted skulls that are more prone to injury and brain damage if pecked. Also because they look unusual, the other birds are more likely to peck their crest. Males hold onto the back of the head to help balance whilst they mate. Young cockerels are less balanced than an experienced roo and young pullets don't know what to do and often struggle to get away from them, which is when injury (sometimes scalping) can occur.
Were there any specific reasons for getting some cockerels? They really change the flock dynamic and not always for the better so without knowing your goals, it's difficult to advise.
An older experienced rooster is a better bet with young birds. They are normally much easier on the hens and you have more idea of temperament than getting adolescent males that are unpredictable and often insatiable with their sexual appetite.