For the missing zerks look in the hole to see if part of the zerk is broke off in there, if its not then you can get some new drive type/press in fittings and knock it in with an appropriate size socket or small pipe. You might even be able to leave the broke end in there and just drive the new one in, I guess grease would still flow.
One of mine was broke off in the hole so used a small drill bit to get out as much as I could, probably would have been good to take the bolt out and reverse flush with some brake cleaner, but I didn't. The greasable bolt on mine used 3/16'" drive type fittings.