Yes it does! Put a floor jack under the tranny immediately, your motor mounts are the only thing holding up your drivetrain with the skid plate removed. There is a rubber mount on the skid plate that the tranny mounts to that holds it in place.
But seriously yes, the skid supports the tranny/t-case. Don't drive it around like that.
Nice... OMG! Do it now was not an overstatement really. That's a lot of pressure to put on the motor mounts. The sense of urgency was to save the OP's motor mounts, but I see that he isn't logged on... Humm, well maybe your right then, the motor might fall out, LOL! No worries, the front axle will catch it.
Oh well, he'll most likely find out when he fires it up, before reinstalling the pan, so he can hear how pretty it sounds. The roar from the fan going through the shroud and rad should be pretty impressive.
Ah Houston, we have a problem.
97 Sahara, 74 Renegade, 72 CJ5, 55 Willy's (the Beast) Boss 302, 6:34 gearing, Bose 901 speakers.
God I miss that Jeep. Forgot the kinda Jeep, 80 SX4.
There is one more support for the rear of the transmission, the hanger from the exhaust system, so it's not just supported by the engine mounts. Granted it's not much but it works fine to prevent damage to the engine mounts so long as it's not being driven like that.
The engine/transmission/transfer case assembly is supported at three points, like a three-legged stool. The two engine mounts and the transmission mount that rests on top of the transfer case skidplate.
__________________ Remember that having a different opinion doesn't also require one to be a jerk when expressing it.