I can play slow individual notes fine, I can get the slap and the pop sound decently, but if I alternate fast between a slap/pop/slap/pop in a quick sequence like slap-root/pop-octave/slap-root/pop-octave, I find that my slaps do not ring out properly. I think it has to do with my thumb position and the movement of my hand. When I slow down the movement it is fine but it feels like I couldn't speed it up.

Is there some way to make a smooth slap then pop motion so that my thumb doesn't just stay on the string and mute it when I try to do the pop quickly afterwards....? In order for my slap to be heard, I have to do a separate slap, and then a pop after. I think it might be from not turning my wrist enough but I can't really seem to fix it?

I'll try to explain further if you guys don't really get what I'm saying.
This might sound a little obvious, but is your fretting hand holding the neck in a death grip? Maybe you need to just relax a little! Possibly, if the notes are 'choking' maybe you need to take care about the position of your fingertips relative to the fret.

Besides, slap is a percussive thing anyway, it's not always necessary for the notes to ring out. For me, it roughly equates to slap=bass drum and pop=snare. Many players view it so.

make sure ur thumb is placed well over the fret board and practice getting ur thumb to automatically bounce back off the string by getting a peice of wood and basically slapping it until u get the automatic bounce back kind like a drum stick. dont be popin' too hard and all else i can say is practice
practice, practice practice some more. Just grab a metronome, write a pattern and start slow, speed will come with time. And the slap is supposed to be more muted, but just play it slow and watch your hand and see if you notice your doing anything wrong.
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I think your problem is very simple.
If you pop after a slap its very important that between the two notes the thumb will stay on the neck, and the pop will be in the same motion as the thumb raising.
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You should be ready to the pop the moment before the thumb hits the string. As your thumb is coming down you should already be in the process of getting those fingers curled beneath the string to be popped (I use to fingers because I usually play things with double pops)