You shoud be able to identify the owner's name and then track her down by contacting nursing homes. As previously mentioned the mail is being forwarded to someone.
A little serious junior detective work may pay big dividends.
I recommend sending a letter to the homeowner; however it is important to note a few possible scenarios. Given the possibility that the homeowner is in a nursing home, their family may be in charge of his/her personal affairs. If this is the case they likely want to respect their family member and their connection to the home. Hence your letter should be tailored to this possibility. Be sincere and genuine in your expression as to why you are interested in the property and how you came to be familiar with it. If you have lived in the area or knew the family from some time ago mention that. Often homes that have been in a family for a long time holds memories and when dealing with such a scenarios as the one you have mentioned sensitivity goes a long way. Appeal to both the financial and condition aspects of the property sitting vacant while reflecting you respect for the possible emotional ties. Donâ€™t need to be a bleeding heart or a wolf out for a good deal.
Be aware that the estate lawyer is under a legal obligation to respect the confidentiality of his/her client and this may be why you have not heard back.
You may reference the following pubic information sites in order to correctly identify who you need to be speaking with. Address the letter to the owner found on the information you get from either of these sites. This is how the government reaches them. The Maryland department of Assessments and Taxation