I have to agree with Puffer Punk and Mubu on this one that it looks more likely to be a unusually marked fahaka... although still a very nice fahaka at that... since every time i've ever seen a Cross River the spots had been more pronounced and not stripy...
As for tankmates, in all honesty its a gamble as to whether or not any fish will last in the tank with your puffer since it could be fine to begin with, but your puffer could decide to turn on your other fish any where from a week/month/year later with no warning...
So imo, if you must get other fish, you could consider getting some small cheap dither fish which have some speed to avoid your puffers jaws... this way if you do lose any, it won't hurt your wallet too bad...