I've searched the 0201010420 trailing bytes and checked hundreds of private keys manually but with no success as yet. I could see they were bitcoin core keys with the data and text surrounding them. I suspect that the private key I need is encrypted and there are hundreds of those as well, plus mkeys. I noticed that each ckey marker 000104636b65 79 is followed at a point later by the trailing byte of 30 as discovered and shown in HCP's example. I'm thinking that maybe the bytes following 30 is the encrypted key and the public key is between 79 and 30 maybe?
If you can grab the entire block of encrypted data from start to end then you can decrypt it using standard methods in which you start with your IV (Initialization Vector) so from the start and not like a partial/damaged or orphaned block in which you need to use the chain code from the previous block.
From what you wrote it seems that the data is still intact so there should be no problem to find it.