Helen Keller comes to mind as an example of a human experiencing similar conditions to your creatures. I seem to recall that before being taught sign language, she could still make herself somewhat understood, though that may be because her family could see/hear. So I'm going to throw out this example for the rest of this answer.
Instead, I want to imagine how these creatures would live. For one thing, if they're loners, they're not going to develop language no matter how easy it is, so let's assume they're pack animals. Thus, they will sleep, move, and eat together, and feel terror when they are alone. For these reasons, I imagine that much of these creatures' time will be spent in physical contact with one another (think of people walking in a snowstorm, or WWI soldiers blinded by poison gas in long lines, holding onto each other for direction). It may be possible that a group will never let go of one another, forming lifelong partnerships with the individuals in front of and behind them. They're going to end up knowing a lot about these two people, and should be able to tell their mood just by feeling their body language-- that is, if they have body language at all.
I think rather than a static line, it's more likely that individuals will remain connected, but often switch their place in the group. That way, the alpha can make sure no one is plotting against them, and no one has been left behind. Also, it allows the young to learn from a variety of sources. This way, I think body language will develop, as there are certain things individuals will want to tell each other (for instance, "I don't want to hold your hand", or "don't leave, you're not as sweaty as the other guy"). This may come in the form of hand signals (like soldiers entering a building tapping each other's shoulders), or more subtle cues like posture. Keep in mind that without most senses, these creatures' sense of touch should be much more precise than ours, so they should be able to pick up a variety of cues that we couldn't, such as small changes in heartbeat or hairs standing on end.
Whether or not this all turns into a form of communication that we would call language is debatable, and mostly based on the potential these creatures have for intelligence. However, with the example of Helen Keller again (I know, I said I wouldn't bring her back up, but she didn't hear me when I told her to leave), she learned to understand sign language by feeling it, so sign language could be used by these creatures to communicate as long as they were smart enough to develop it.
As for written language like braille, I think it should develop eventually, just like written languages did for humans. Come to think of it, it may develop earlier: these creatures should already be used to combing the ground for familiar paths and handholds, it shouldn't be too much of a leap to place certain objects with special meaning in places where they will be found. This may start as a way to more easily find places, but could evolve, again based on the intelligence of these creatures.
