Nope, both cases I was down to my 5 vs their 4. I can see no reason as to why deathmark did not stick. This is a big deal as deathmark is a sure kill and I use it frequently against elite versions of the rebels since they are so tanky.
Neither enemy had foresight either. It should have applied both times. I hope the devs read this stuff here. I tried looking over the suggested bug report area and that is confusing. Like most online help centers, they are designed by people who understand the products/services well without consideration for those who don’t. Therefore I’ll never be able to report anything there....they should have left the bug section as easy to post in as I post here.