1. There is no "case law" that says what you think it does. Article 4 section 3 most certainly does apply to federal land within states.
2. Even if your argument was true (it's not), the Nevada state constitution also explicitly gives control and ownership of public lands in Nevada to the federal government.
If what you're saying is true, how come people living on all that Federal Land are considered Citizens of Nevada and are able to vote and receive Nevada driver's licenses? Should these people be be of the same legal status as those in Washington DC?
Oh right, they don't have the same legal status as DC residents, because Nevada is the Sovereign of all US territory contained within its boundaries.
Do Nevada's laws become null and void on these federal lands? If I commit a violent crime on these lands, am I charged under federal law or Nevada law?
Are people living on these federal lands barred from voting in Nevada elections?
See your train of thought is inconsistent with reality.