Error in E3M6 briefing

[gsilver0]

Steps to reproduce: Start game with: RAD -warp 3 6

To go directly to episode 3, level 6. At the end of the first page of mission briefing text, game crashed and the following error appeared:

W_GetNumForName(): eg1 not found!

The game may be played as normal if the player immediately hits escape to skip the briefing and go into the game. This issue is also in the OpenGL version.

I didn't see anything unusual in Radix_stdout.cachedbuffer, but a copy is attached. Radix_stdout.cachedbuffer.txt