Gypsy vanner colt

Hi everyone! 

First, I have to apologize myself - I'm here new, and come from Czech Republic, so sorry for my english :)

I need a little help about my friend's foal. It's little colt, almost 4-month old, Gypsy horse (Irish tinker/cob). Both his parents are black tobiano with roan gene, sire has maybe something for chestnut (not sure - we haven't tested him yet). Colt has very amazing colour - newborn he looked like a silver, now he's black with white/beige mane and tail. I'm pretty sure he's sabino too. 

But... is it even possible, he's silver? Or he is "chocolate palomino" - liver chestnut with flaxen gene (if yes, what will he "transmit" to his children - will he be coloure-interesting for breeding)? 

Or am I just wondering and he's going to be only black? 

Thanks all for every help. 

Photos are order chronically. Last photo sire.