Concerned with what a "technician" might have done

Hi everyone,

So a key on my Macbook air is loose and I need to get it replaced. Not a big deal, this has happened before. However, I am living in China and I don't speak the language well enough to deal with these things in Chinese. I asked a friend to accompany me to my Apple appointment and apparently we wound up in an unauthorized shop. Although I had a proper genius bar appointment, he took me to the wrong place. Not realizing this, I let the "technician" there look at my computer. He took it in the back for a few minutes and said that there was "massive water damage to the battery" and that the "entire keyboard needed to be replaced before he could look for the problem." He had the screws in the back unscrewed and was playing with something under the back cover when he took it back out to us. He seemed to have something detached and then reattached it. After belatedly coming to realize where I actually was, I told the technician that I'll take it elsewhere.

I went to my proper genius bar appointment in the right location. When I turned the computer back on, the time settings were out of whack and my Microsoft Office was telling me it didn't recognize my subscription. The real Apple techs fixed this problem, but I am worried that the first technician may have done something more to my computer. I know there was no water damage because I had it checked out just a few weeks ago and all has been fine between then and no. I am concerned that he may have inflicted further damage on the machine. Perhaps I am just being neurotic. The unauthorized technician was only with the computer for a few minutes, but still I am a bit concerned. My computer seems to be working fine now, but still I am worried.

Is there anything major that the technician could have done in the span of a few minutes that will have lasting consequences?

Thanks in advance.