I experienced this bug today! Again, with Yareli. I have noticed that when I'm hit by a grineer Bombard's rockets while I'm on Merulina, it gives me about 20 separate blast debuff markers all counting down, but they usually go away. However, today, I had exactly what you have in those first few pictures, several blast debuff markers showing 1.0, one with a timer counting down, and then a stack of several hundred that kept growing. I'm not sure what exactly caused it to start, I assume it has something to do with those strange blast counters initially and then something interacting with them. I was at rank 30 the whole time through, so it wasn't caused by that. I did not experience the health increasing with arcane blessing, and didn't notice it increasing stacks of my molt augmented.
Very strange occurrence, to be sure!