While there are many trademark questions that can be answered with common sense or a basic understanding of the issue at hand, I think pursuing something related to an abandoned trademark is definitely something that should be done in consultation with an attorney.
Abandoned as a registered trademark may not mean that it is abandoned as a trademark in a larger sense.
Another red flag is that, in your original post, you did not present a case where you are pursuing this name for a use in a different class that does not infringe on the abandoned trademark, so it seems likely that you are pursuing that name based on the value of it as built by the original trademark holder. And, if true, that sounds like a major issue.
This is definitely one for a lawyer.