Ssh – Cannot reattach to a screen session after SSH connection was dropped

I have previously reattached to a long-running screen session with screen -dr control. However, sometimes this command will not reattach to the screen and instead hang forever (10+ minutes after which I aborted). This only happens when the SSH connection is dropped unexpectedly and not when the screen is properly detached with Ctrl-A d. Other switches, such as screen -x or screen -D -RR also do not work.

This post suggests to kill the PTY that holds the screen session which will cause screen to complete its disconnect. However, it simply kills the shell from which screen -dr control was called.

For example:

$ ps -ef | grep control | grep -v grep
nomad     7387  7109  0 13:05 pts/50   00:00:00 screen -dr control
nomad    15299     1  0 Nov27 ?        00:13:47 SCREEN -S control

$ ps -ef | grep bash | grep 'pts/50'
nomad     7109  7108  0 12:49 pts/50   00:00:00 -bash

The linked post suggest to kill the bash process with PID 7109. This will also kill the screen -dr control process with PID 7387. Afterwards, I still cannot connect to the screen.

The process SCREEN -S control which started the screen session has init as its parent which I obviously cannot kill.

Is there a way to reattach to the hung screen session?

Update: This happens on CentOS 6.4 using kernel 2.6.32-358.6.1.el6.x86_64. The shells are all bash version 4.1.2(1)-release.