I Also Believe That Leo Looks Genuinely Concerned In The First Image And Once He Hurt Donnie, Especially

I also believe that Leo looks genuinely concerned in the first image and once he hurt Donnie, especially with the sweat droplets on his forehead. Of course it can be argued that he expressed these emotions on purpose, having shown his acting skills in previous episodes, as well as being the face man.

Futhermore, with the head cannon of Leo being the medic, makes it highly unlikely Leo would intentionally injure one of his brothers, let alone Donnie as a softshell turtle. If The hc was canon, then Leo would have grown up treating his brothers' injuries, even if they were never that serious. However, since Donnie is a softshell and bruises easilier, all of his brothers would want to be more careful to not hurt him.

Thus, makes it more probable that Leo did not intentionally hurt Donnie.

An ongoing debate within the fandom is whether or not Leo fell on purpose during the episode Lair Games

Leo: Donnie? Donnie are you okay?

Donnie: You did this! You’ll do anything to win! My ankle! My moment!

Some people have said that Leo might have fallen on purpose in order to win due to his competitive nature while others have said that Leo looked too surprised at Splinter declaring him the winner of the event to have fallen on purpose. 

Splinter: Purple hit the ground first! Blue wins!

Other arguments used for Leo having not fallen on purpose are that the fall most likely hurt for Leo as well as Donnie & that Leo would never intentionally actually hurt a family member considering how important family is to Leo. A counter argument for this have been people saying that Leo didn’t mean to hurt Donnie by falling & that was the only part that was an accident.

However there is a piece of evidence that might mean that Leo did not fall on purpose & that is his family thinking that he did do it on purpose.

Mikey: And that’s when Leo fell, or did he?

April: So you think he did it on purpose?

Mikey: [Nods]

Donnie: It was Leo! He did it on purpose!

Leo: I’m only talking to you to set the record straight, I didn’t do it on purpose! I mean how could I? I had half a fridge on my chin!

Donnie: I’m sorry can I have a moment?

In the episode Lair Games most of the Hamato Clan seem convinced that Leo fell on purpose with Donnie & Mikey even saying so & April arguably taking Donnie’s side in the interviews. However a running gag within Rise is that whenever one of Leo’s family members try to make assumptions on what Leo’s doing we’re shown Leo doing basically the opposite of what they’ve just said.

Raph: Hey! Where’s Leo?

Mikey: I’m sure wherever he is, he’s trying to save us

Raph: Leo probably talked his way straight into Big Mamma’s dungeon 

Whenever Leo’s family tries to predict what Leo will do, Leo’s family is almost always wrong whenever they try to assume Leo’s actions. In contrast when Leo tries to guess his families actions, he is almost always right.

Leo: Look I bet the only reason we’re here right now is ‘cause Donnie inputted coordinates of blah blah blah

Donnie: After inputting Shredder’s previous coordinates on the X-Y-Z and D for Donnie axis, I have calculated that this is the sight of our final resting spot. I mean go team?

Leo: Mikey Razzed his Tazz

Mikey: Whip-o-Rama!

Leo: April finally used her crane license

April: ‘Why would you get a crane license April?’ BECAUSE THIS!

Leo: And Raph is going to put it all together in a plan to defeat that led head with this mystic collar

Raph: Wow Leo that’s remarkably accurate

Raph: He’s back. Prepare for Operation Fire, Hanky, Tickle, Collar!

Leo: Yeah!

It is a slight running gag in Rise is that Leo is able to predict his families actions to a near perfect degree but whenever his family try to predict or assume Leo’s actions they are almost always wrong to a near comical degree, meaning that Leo’s family assuming he fell on purpose in the episode Lair Games might actually be evidence that Leo fell by accident instead.