Progressive melting continued over many burns.  A pool of hot gas forms under the enclosed section of nose, melting the highest windows.  The windowed rear panel deforms quite a bit over time, despite the film cooling.   The hot air gun can temporarily restore the melted parts.

There could be more stringers on the inside.  It would be impossible to apply epoxy there.  The inside of the nose is thinner than the cylinder.

There could be epoxy under all the windows.  Then the windows could be manually drilled out again.  It would be expensive.

A hole in the top probably wouldn't vent enough.  Past experience showed it still pools.

Then there's CA gluing around all the trouble spots.

A little hole on top got it pooling slightly less behind the windows.  The hole & CA glue might have slowed it down, but it still melted.

This whole PETG idea might be busted.

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The winners of a backflow incense assortment were Lily & Osmanthus.  

Unfortunately, getting those affordably required ordering a bunch of awful flavors.

Lily is not sold separately but osmanthus is available for a price.