Definitely the Highlander. The average 16’
Scamp weights around 2600# loaded for travel, and tow ratings assume an essentially empty tow vehicle. Not much margin for extra gear and/or severe towing conditions (mountains, elevation, temperatures, wind).
In fact, if you can find one in this crazy market, I’d suggest a used 2019 or earlier Highlander hybrid with a V6 gas engine. Starting 2020, it has the same 4-banger as the RAV4. The tow rating is unchanged, but I doubt it will perform as well as the V6 on a long grade in the mountains.