Unfortunately, Kai, you haven't been here in two years or more according to this comment, and I have no idea whether you've learned this somewhere else; but for those who pass through and see this, you and they should know that the answer is NO. The letters להת (pronounced l'hít) in להתראות are a clue that you are looking at a hitpa'el infinitive - it is reflexive. We modern Hebrew speakers use this particular word to mean "see you later" or "see you soon" but it literally means "to see oneself."
I hope this helps!
I don't know for sure, but it wouldn't surprise me at all. Hebrew seems to have been more fluid than modern English with regard to spelling, other than the shorashim (word roots). Or, maybe the person who wrote or designed the sign you saw just didn't know how to spell it! That would have to be confirmed by someone who knows Hebrew better than I do.
As a programmer I know why your sentence was turned around. You typed in hebrew this is right to left. Then you typed in german which is left to right. To teach the computer to recognize the change is quit a bit difficult. Should be doable but less programmers take the time to do so cause usually you wouldn't change so often the reading direction. Thanks for your comments and questions much in the comments here and in other parts helped me a lot learning the language better.