Does dodge ram 250/3.9/1994 dodge ram Van have a starter ground

I know you said it isn't the battery, forgive me, be sure the battery has a full charge and battery connections all good. Use a test lite and follow battery voltage. Battery ground is important also.
The battery voltage may lead to junction block--fusible links--fuse box?
At the fuse-box, pick any component that has a fuse, check fuse circuit for voltage, use a test lite. Some fuses are hot all the time, some go hot with key on, test both ways.
If the starter motor won't crank, check voltage and ground for the starter motor. Usually two voltage circuits at the starter motor, one comes from the battery, hot all the time. The other circuit goes hot with key in the crank position and is probably wired through the clutch or neutral switch then through the starter relay, where applicable, to the starter motor. The starter motor usually grounds through the engine block, so, battery negative connection is important.
Any testing at starter motor, make sure tranny is in park or neutral and functional parking brake is set. Safety is your responsibility. You don't want the vehicle to move during testing.

I would start checking fuses for power. It could be a battery cable issue or something in the fuse box. The dash lights would not be powered thru the key switch, but the other stuff would be. Provided the key switch is getting power for accessories.

try the ignition coil connector and the ground on the coil which is through the screws holding the coil on, i removed and reinstalled the screws with lock washers to help the ground issue

Under hood in black box by battery most likely. Should also be listed in you user manual.

check all of the grounds, battery to engine, battery to body and so on

Try boosting the van.If that works then you either need to clean the cables and battery posts or you need a battery.If boosting it does not work then you may need a starter or the cables to it have came loose,also the engine ground could be the culprit,if this is true then put your booster cables in this configuration;positive to positive and negative from the boosting cars negative post to your engine's block,find a good clean grounding point on the block and hook the clamp there.If the van starts then clean the factory ground point,replace the cable end,or replace the cable.Let me know if none of this info helps and i will give you more things to try.

i know alot of crysler/dodges had a crank sensor i had 1 go out on mine check see if you got 1 chances are thats it when mine went out it would turn over but no spark

Under your van, mounted to the transmission bellhousing....please look at the photo.

Park van so that you can safely access the starter. I use ramps under front wheels and put it in park and set the parking brakes. Disconnect positive battery cable at battery, disconnect starter battery cable and ignition wires from starter solenoid (remember terminal locations as these will attach to new starter solenoid). Remove old starter. Replace with new starter. Re-attach wiring in reverse order.

ALWAYS CHECK THE GROUND ON A DODGE