First the options of selling fun tokens now and buy back later doesn't make sense because if the freebitco comes back to normal state the price of fun token will rise.
I don't really think it's worth to invest in FUN tokens.
Each token was worth around $0.03 at February 01, 2021, when it became available for buying on freebitco and now it costs only $0.0045. That's around 85% decrease (and even more if we consider the FUN/BTC pair).
The decrease in FUN token price isn't only due to the issues now going on with freebitco and that's why I don't expect to see a significant recovery in FUN price even if the issues are solved. The issues with freebitco started in May 2024 when FUN token price was around 0.005$. This means that the FUN token had its crash when everything on freebitco was working well.
Investing in FUN tokens right now is indeed risky, it can maybe get a massive pump without any reason but chances are higher it would just drop to zero. As you mention, when they launched the FUN tokens years ago, the price only went downhill so even if all issues are solved, why would the FUN token price suddenly get higher?