All I can tell you is that the crash was in the Intel driver mfx_mft_h264ve_32.dll whilst Plex Media Server was testing it out to establish if it is available to be used
Apr 05, 2019 19:58:33.444 [8172] DEBUG - Codecs: testing h264_mf (encoder)
Apr 05, 2019 19:58:33.705 [8172] INFO - [FFMPEG] - MFT name: 'Intel® Quick Sync Video H.264 Encoder MFT'
and it crashed at this point
You could check installed version to see if there is an update available from Intel
Last time we had crashes in this dll were when PMS was run as service/RDP - so i thought it might be the same