Well of course I can't speak for your husband's company, but if it was a tax equalization package, the only way it could have worked is if they did all tax returns, otherwise how would they know how to equalize the tax?
You are saying tax preparation, so I don't know if it included equalization as well, but still I would have thought, like you that it would include all countries where taxes may have been owed and often times you can't do one country properly without doing all countries. We had some US/UK/Germany/Ireland folks a few years back... We gave PWC a major accounting headache.