She must have forgot me vs She must have forgotten me

Some examples from the web:

• I'm sorry, I must have forgot.
• Guess our boy must have forgot that.
• Chelsea, Chancellor Agrippa must have forgot to clear me.
• They must have forgot to lock it.
• Whoever was covering his tracks must have forgot to look there.
• I guess we must have forgot.
• I guess we must have forgot.
• She just must have forgot the way you like to be petted.
• Ed must have forgot to pack those M.R.E.S
• Ed must have forgot to pack those M.R.E.S
• I can't believe the waiter forgot me.
• They forgot me at the service station.
• TV never forgot me at the zoo.
• I thought you'd forgot me.
• You forgot me, Andrea Yates.
• You went to California and forgot me.
• I got all the way downstairs, realised I'd forgot me coat.
• Plague upon it, I have forgot the map.
• I figured he might have forgot.
• Ones which I am surprised you have forgot.

Some examples from the web:

• No, she must have forgotten too.
• She must have forgotten to swipe her card on way out.
• Patrick must have forgotten the thermostat.
• I told her that yesterday, but she must have forgotten, which I know sounds like an excuse, and I am sorry for that too...
• They must have forgotten about him.
• Sorry, I must have forgotten to enter the mileage.
• I must have forgotten to take my pill tonight.
• I must have forgotten my wallet in my other car.
• Then I must have forgotten them.
• I guess I must have forgotten all my bad habits.
• I always hide the keys. I must have forgotten.
• I must have forgotten to put it back on after our massage.
• Sorry, I must have forgotten your water.
• I'm sure I must have forgotten something.
• He must have forgotten how to turn off the faucet.
• It's been a while, I must have forgotten.
• I must have forgotten there was a camera.
• Must have forgotten my jacket then.
• I must have forgotten to close the door.
• Must have forgotten my Bill of Rights at home.