Because she's 2 years old and coming over with "covered" bruises...here's what you need to do.
Go out and buy her a "pwetty" new outfit. (before you pick her up)
When you get to your home, ask her if she wants to put it on. If it's "weawwy weawwy pwetty" she will. Get her undressed, and without her knowing, quickly give her body a thorough look over. If she doesn't want to get her new outfit on, tell her she's "bewwy tinkie and needs a bubble baff" If you see any marks that look more than your usual 2 year old bumps and bruises, say this...
"doodnes dwacious, dass a pwetty big owie you have there..." I'm serious..stop laughing. Be all types of excited and "dork" like when you say that. Make her interested in this owie. But don't say anything AT ALL after you do your childlike questioning.
If you "got" her interested, she'll probably tell you what happened. Don't prod, don't ask questions, just be a great big silly person. If she says anything at all like "mommy kicked me" just say something equally as silly as the first thing you said..."holy moly, sugarbear, that must have hurt!!!" And then drop it.
Run, don't walk, but fricken RUN to her doctors...if they're closed, bring her to the ER. Now, no one jump me on this next part...I do NOT care what your court orders say. I do NOT care if they say you will go to jail forever if you take her to a doctor...GO ANYWAY!!!!!!!
The OOOOOOOOOOOOOOOOOOOOONLY time I ever got help for my son is when I did just this. I picked him up from daycare, and on the bus home, he happened to look up. I immediately noticed the "hickey" around his neck...looked like a thin hickey necklace...IOW..he was strangled. I did the whole excited thing I told you to do, so he told me what happened. When we got home, I called his doctor who for some strange reason, set his appointment for the next afternoon, but informed me she's immediately calling social services. (on my word that some type of abuse happened to him) A social worker was at my house within an hour talking to my son...She made her report, and investigated the daycare center, as my son told her what happened there. At his doctors appointment the next day, they ran this blood test to see if he was an "easy" bruiser. He wasn't, and the doctor determined that "whoever" did this used excessive force.
My point? Don't bother with 911, don't bother with social services YOURSELF. Go straight to the doctor/ER and have them do it. I can't tell you how many times I've called the "child abuse and neglect" hotline, and social services, and the police for welfare checks...NO ONE CARED!!!!!! It took me calling his doctor before anyone gave a damned.
I've called for a police welfare check when my son showed up at the supervised visitation center with a shiner like you wouldn't believe. He was CLEARLY socked in the eye, but what monster told the center was that "he fell on the bedpost"...and my son shook his head yes. That was good enough for them. I, however, BOUGHT that particular bed, and the bedpost was 4 X 4 and square...half his face would have been bruised and cut...not just a single shiner. That night, when I finally got home, I called a police welfare check. Monster refused to answer the door for 15 minutes, so I gave them his phone number. He answered the phone, but took another 10 minutes to open the door. He said the same thing as he told the center, and my son just shook his head to agree. No one cared.
I've got more horror stories, but I won't go into them. Call the fricken doctor when you see ANYTHING...especially if it's covered up with make up. Now, about the foundation covering it up. You can still see bruises under that...trust me, it doesn't cover bruises or pimples. Do NOT wipe it off! Let the doctors see exactly what your ex is doing. oh, when you do take her in, they'll ask if you suspect anyone of doing this...DO NOT, I repeat, DO NOT tell them it's her mother...say that you picked her up from her moms...but you've no clue who did it.
This sucks for you and your child...I'm very sorry.