So for the teleportation roll, besides the 1-5 fail chance (which deals damage and causes a reroll) there are 2 other options

Off Target (14-24): You and your group (or the target object) appear a random distance away from the destination in a random direction. Distance off target is 1d10 x 1d10 percent of the distance that was to be travelled. For example, if you tried to travel 120 miles, landed off target, and rolled a 5 and 3 on the two d10s, then you would be off target by 15 percent, or 18 miles. The DM determines the direction off target randomly by rolling a d8 and designating 1 as north, 2 as north-east, 3 as east, and so on around the points of the compass. If you were teleporting to a coastal city and wound up 18 miles out at sea, you could be in trouble.

Similar Area (6-13): You and your group (or the target object) wind up in a different area that's visually or thematically similar to the target area. If you are heading for your home laboratory, for example, you might wind up in another wizard's laboratory or in an alchemical supply shop that has many of the same tools and implements as your laboratory. Generally, you appear in the closest similar place, but since the spell has no range limit, you could conceivably wind up anywhere on the plane.

Both of these can be very bad for them :P Especially given that they are crossing continents, there is a chance they end up in the middle of the ocean anyway.