Hi,
No, he wasnt married twice, in the indexes there are usually 2 or 4 couples to a page. Harriet Tittles was the other bride, but she must have married the other groom listed if Job married an Ellen.
The marriage certificate will confirm if these are her parents, or a birth certicficate of one of Job and Ellen's children will confirm Ellen's maiden name.
My Downings are complicated. I think they briefly changed their name for some reason from Dunning to Downing and then back again

Your Downings dont sound familiar unfortunately (my John Downing/Dunning b.c1819 was a flower painter potter Wolstanton area, married to Hannah Vickers)
Let me know if you need any more lookups
Regards
Catherine
