So my question, which is going to be the biggest question is how much did you pay for him?
If he is "double het for ghost" (whatever that means) then he should of had a fairly hefty price tag.... If you paid normal prices you get normal snakes.
A het is a het, meaning you cannot tell by looking at it. If you were not given instruction as to its genetic background then there is none. If you think there may be something different about the animal don't put a label on it. Breed it to find out, THEN label it.
And who cares who or where the animals came from. You have 5 snakes now, but if you get the new snake and it has any issues that number could drastically drop... back to ZERO. Quarantine is the safest way to introduce new members to a collection. RI and mites are the first things, but definitely not the worst things that are contracted from non-quarantined animals. BE SMART!