I spoke with TD Bank this morning. Their tech support told me they're only supporting Quicken and that this issue will need to be addressed by the MoneyDance developers. Terrible answer but hoping this can get resolved!
I'm afraid our development team still haven't gotten to the bottom of the TD Bank connection issue and for the time being TD Bank is still not on our list of supported banks. We do still hope to re-add the connection in the not too distant future, I'm sorry I don't have better news regarding this.
In the past, I was blocking tmx.tdbank.com with my web filtering program, without any problem entering the site. I am suspicious of any connection outside of TD's domain. Some time this year, I started having a problem, and had to allow the connection.