Marco is stronger than both King and Queen individually, but obviously not strong enough to deal with both of them at the same time while he pays attention to people he's curing while fighting; hence why he's so exhausted. The portrayal in 1006 is good enough in Marco's support to believe otherwise (a chapter with a huge inconsistency, by the way, if anyone want to go and find it), in which he was pretty much playing with them.
Queen never landed an attack on marco.
King cut his wing with fire bullets and a second time with his sword.
King damaged marco with the fireball.
King >> marco.
Queen pierced Marco multiple times with his mouth's gun, and when he lasers him (and arguably exposes him while dodging for King to slash his wing) he may have hit him too since the right wing is abruptly discontuned (but could be a drawing inaccuracy).
Anyways, it's a lie that Queen never landed on Marco.