Added reverb tail disappears after export

I think I found the actual solve fo this, without having to do any crazy render hack. The trick is that instead of adding a black video or disabled clip to extend the tail, take a part of the audio clip, duplicate it and then "mute" the audio by dragging the level down all the way to -infinity. This worked for me, hope it helps!

Hey Fellas. I know this is late but just wanted to share the solution because I ran into this a couple times in the past year or so.

The solution for me is to... "render" the audio. In reality there's certain audio effects that premiere doesn't render even if you select your in and out and hit "Render audio".

What you have to do is set your in and our over the area with those reverb tails, and go into preferences and make sure "Render Audio when Rendering Video" is checked. It's somewhere in there. It's moved around in the past couple versions. Then Render Video. As far as I know this is the only way to force premiere to "render" those reverb tails and have them come out on export when it's acting funky.
There are a few other audio effect things that come out wrong on export that this workaround fixes.

TLDR:
make sure "render audio when rendering video" is checked. Then render video over the section of audio you need to fix for export. Render Audio might work too, but this preference has to be turned on.

​You might want to turn it off when you're done. Because it can make rendering slow as all hell otherwise.

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