I think it's more a 10-15 minute walk from the entrance of the Marriott to Hertz, as Hertz is at the far end of car rental row. But it's definitely walkable.

If someone is dropping off at Hertz & walking back to the Marriott, you could ask the Hertz driver to drop at the corner across from the Marriott. Not sure they'll all agree, but some will.

I had one do that end of March, although he actually dropped me at the corner across from the Ren. Normally that wouldn't be a problem but immediately after the drop-off it started raining hard & by the time I passed the 4Pts/turned onto the Marriott property & got to the front entrance I looked like the proverbial drowned rat!

Cheers.