Jerry
If the hubs were actually locked then is the drive-train engaged further back? Perhaps one of the vacuum lines may have come off the diaphragm 4wd actuator? Are the two buttons, 4wd & Front hubs, each turning on a separate light on the dash?
Suggest you check in both 4HI and 4LO separately as the 4lo will engage 4wd without the 4wd button pushed . Put into 4wd and then drive a little and park on a decent surface.
Chock vehicle to avoid another of our friend’s dramas

and then jack one wheel so it is just off the ground or preferably on an axle stand.
Crawl under your truck and attempt to rotate the front driveshaft. If you can that means that the front drive has not engaged and the problem is likely to be at the actuator diaphragm, a dia. 80 device located just in front of the Transfer case on the LHS. These vacuum lines go to two solenoids located above the brake booster on the driver’s side of the fire wall on a 1KZ-TE versioned Prado.
Hope That helps
John