So based on the information we've been given, the values we need for each keyframe are:

• servoOne null, servoTwo null (start wherever the servos happen to be)
• servoOne 0, servoTwo 180
• servoOne 180, servoTwo null (servoTwo starts moving towards 90 degrees)
• servoOne false, servoTwo null (servoOne stays put, servoTwo still moving to 90 degrees)
• servoOne 90, servoTwo 90

Each position needs to be an object with a property degrees for each keyframe. Let's translate that into JavaScript, right under the construction of our animation object:

let keyframes = [
 [null, {degrees: 0}, {degrees: 180}, false, {degrees:90}], // servoOne
 [null, {degrees: 180}, null, null, {degrees: 90}] // servoTwo
]

Now that we have our keyframes programmed, let's get started on our cue points.