Is there any risk to using Crossover instead of natively running Windows (e.g. via Bootcamp)?
Using Crossover Office to run a couple of Windows programs on your Mac usually works quite well, IF the program is specifically supported by Crossover. If it is not specifically supported it may work but some features may not, it might crash, etc.

Not sure what you mean by "risks." Though I don't use Crossover Office (or the open source that it is based on: Wine) it emulates part of the Win32 API allowing Windows programs to run outside of Windows.

This may be safer than running Windows in a virtual machine (Parallels or the free Virtualbox) as you don't have the whole Windows environment that may need continuous updating/patching or even it's own virus checker.

But generally speaking I have heard that Crossover Office is a reasonably well working app that does what it advertises with minimal issues.