Read the documentation carefully. A state court can't restore federal rights. You may be in the unfortunate condition of having your right to possess a firearm permanently stripped.
18 USC 922(g)(9) ... has been convicted in any court of a misdemeanor crime of domestic violence.
I can't tell from your description if you were ever convicted of a DV misdemeanor, and you note having "that ... conviction dismissed."
I recall reading a case where a fellow was convicted of the FELONY of possession, even though he thought the state restoration of rights paperwork was a full restoration of rights. It was a full restoration of Minnesota state rights, which the feds have no care, concern, or respect for.
See my July 15, 2010, 7:20 am remark (#185) at volokh.com, in a thread carrying the title "Seventh Circuit Upholds Ban on Gun Possession by People With Past Convictions for 'Misdemeanor Crime[s] of Domestic Violence'"
Not so. As it stands at the moment ONLY a state court can put you right with the feds. If your rights are restored completely by the state with the original conviction (and it must be completely, including the right to vote, serve on a jury, and so on, and it must specifically mention restoration of gun rights) the feds will honor it. The catch, aside from what I mentioned already is that the restoration must be unconditional. For example, if the state restores your rights to own a rifle but not a handgun, the feds won't recognize the restoration at all, even with respect to the rifle the state says is OK.