"the Wonder Wheel, a Ferris wheel that looked " VS "the Wonder Wheel, a Ferris wheel, that looked"

Above all, we boarded the Wonder Wheel, a Ferris wheel that looked as tall as a seven-story building. (From an ACT test)

I know "a Ferris wheel that looked as tall as a seven-story building" is used as an appositive for Wonder Wheel, but why can’t it be "we boarded the Wonder Wheel, a Ferris wheel, that looked as tall as a seven-story building" where "a Ferris wheel" is still a appositive and a relative clause modifying "Wonder Wheel"？