I genuinely believe that the merc is lying. This is something that I've been thinking about and would like to put it out right here.
Reason 1: Time/Call. Thanos made a call asking the leader to stand down. But not five minutes later we encounter him walking towards us claiming that he has carved Odin and Frigga, and has some liquid medicine that would save them from immediate death. But medical treatment would still be necessary.
He did all this (Hurt Frigga and Odin, meticulously because 'Asgardians are hard to kill.') and moved from the chambers to the outside of the palace within the time it took us to run from Thanos to him.
Reason2: Medicine is not real. How did the merc get hands-on medicine for Asgardians? Their whole biology is different and unique, who would even have medicine for Asgardians?
Reason 3: Betrayal? The most confusing part about this merc? He carved into Odin and Frigga to secure his retreat and force Loki to make a choice. This merc knew he was going on a suicide run. And when he lost his whole company, instead of running (though can't blame him Frigga and he were fighting), he stayed to hurt the King and Queen of Asgard... Even when Thanos called it off. Instead of escaping and taking the weapons with him, he stayed to harm Odin and Frigga and make Loki suffer.
The best part? Thanos doesn't even know that the merc did this.
@KnowledgeKing Am I right in my observations? Or the whole thing is just stupid?