Excellent! I'm glad to hear that they took care of you. One of the reasons I've been so loyal to Marriott over the years is how flexible and customer focused they have been with regards to their reward program.

The rep may be asking you to do some kind of activity because reinstating points likely does not count as "qualifying activity" (not 100% sure of this, but would err on the side of caution that it is not). You might end up in the same position again if you don't get some points credited to the account soon. It's probably worth buying 1000 points just to make sure you're good for the next 2 years.