Is this the kind of place you can pitch a tent or no?

I've seen tents at Guajome.

You can pitch a tent or park an RV at any of the sites. Some sites are better than others for tents. You can look at the park map and compare it to Google Earth to get an idea of what the different spots are like ahead of time if you can't do it in person. Spots 9, 18, 25 and 29 were sites that we took note of for future tent camping as there is more room for tents at those sites. Hope this helps.

Website has tent sites and reservations can be made

I've seen people do that in the reserved camp ground section where the RV's park but I'd call the ranger just to be sure.