Re: death certificates in NJ.
If you can do the search yourself at NJ Archives, you can search year by year up to 1946. Or you could engage someone to do this for you. This assumes that he continued to live in Newark and died there. If you do find the record, the copy itself is cheap.
I would first see if you can get any more clues from city directories. I just did the simple search and found him in 1930. But you might want to do year by year after that and see if you can narrow down his death date. Also, look for Tina/Dina/Eva as a widow. Ancestry has city directories for Newark (with gaps) up to 1957. However, be careful. Don't just depend on the usual search. In some cases, these are only business directories. In other cases Ancestry may have the first half of the alphabet, but not the second. So you'll probably have to check each one. Use the "Browse" section on the right side of the page. Then hop through the directory by guessing page numbers until you find Schneider. Note that some city directories also have residents listed by street address in a separate section, so you might need to check that too. Not a job for the faint of heart, but at least it's already part of your subscription.
Other than that, you might want to get the death certificate for the TAILOR, Valentine Schneider. At least that would tell you for sure that he is the WRONG man.