Walt, Sorry you had to take time for a mission that came up empty. I guess that comes with the genealogy territory. You have to be careful not to jump to conclusions. In this case we had a Joseph and Lena Rabinowitch buried together in a Queens cemetery, with no additional data other than their burial dates. Now of course there were many, many Joseph Rabinowitzes in New York in the relevant years, and there were quite a few Lena Rabinowitzes as well. Where I went wrong was in assuming that a married Joseph and Lena would automatically be our family. The odds say there wouldn't be a lot of Joseph and Lena Rabinowitz couples, but now we know there were at least two.
So I don't think the trip could have been avoided. There was nothing online to suggest that they weren't our Joseph and Lena. Sometimes leads don't pan out. I guess the lesson is not to count your chickens.
I came back after talking to you and did some searches for Joseph and Lena death records using the ItalianGen resource that Morris mentioned recently. They have a searchable database of NYC death records by borough (also marriages). Each record contains date of death and age at death so you can calculate birth year. Therefore it was possible to sort through the scores of Joseph Rabinowitzes to find three or four plausible matches.
Thus we have in Manhattan a JR who died in 1920 at age 65, in Brooklyn a JR who died in 1940 at age 84, and in Queens a JR who died in 1941 at age 85. Any of those would be just about right, and there is one more in Manhattan (died 1917 at 60) that is fairly close. Actual death certificates can be ordered for $10 a pop, but there may be ways to narrow the list before doing that. Also, it is possible that our Joseph's record was not captured in the ItalianGen archiving project, so it could be that our JR is none of those four.
Trying the same technique for Lena turned up three possible matches. Using 1858 as Lena's birthdate, we have a LR dying in The Bronx in 1921 at 64 (1857), in Brooklyn in 1916 at 57 (1859), and in Manhattan in 1948 at 88 (1860).
The other Rabinowitz burial records that I discovered along with these erroneous ones are more definitely valid. Julius Rabinowitz, his wife Annie and son Abner are all at Montefiore Cemetery in Queens. Having just undertaken this expedition, I won't ask you to go on another cemetery visit until it fits easily in your schedule. We know this one will be right because the burial record has Julius' father as Joseph and mother as Lena Lincoff.
Oh well, thanks again. I hope it didn't blow your whole day.