Found the problem! There was a missing space before the FROM keyword. Queries this long/complicated at the end of the day are just asking for a headache.

So, thanks, Norie. While your answer didn't exactly pinpoint the problem, it did point me in the right direction: look for missing spaces at the beginning/end of lines.

The parameterized portion doesn't work in Excel though, I get an error telling me that values for the parameters are missing, i.e., Excel is not prompting for the parameter values the way Access would. I'm going to try to set up some cells where a user can input the information then reference those cells in the SQL. Hopefully that will work.

Wish me luck!