Hello everyone, I decided to take a look at the Blood DK tank macro again and found a spell that it shouldn't be in the second castsequence. It was Empower Rune Weapon, with its big cool-down of 5 minutes, it was preventing it to go into a third round in the sequence and that is why I didn't noticed this earlier. I was able to fix the lock up in the sequence by giving Empower Rune Weapon its own cast line. I must of mixed up the macros in the past while testing new ways to improve it, because I fixed the same problem on the frost lazy macro a long time ago.
I will add this macro update to the addOn plugin as r9.
I'll be back with more soon!