I tried teleporting to w waypoint I had with journeymaps into the spectre dimension after the world was reset. I got teleported to a chunk so I disconnected. After that I tried joining again but I got an error

internal exception io.netty.handler.codec.decoderexception java.lang.indexoutofboundsexception: readerIndex(51) + length(2) exceeds writerIndex(51): PooledUnsafeDirectByteBuf(ridx: 51, widx: 51, cap: 51)

You could try to move your player back to the overworld with an NBTEditor

I’m not the host