Hybrid　systems　that　combine　spin　ensembles　and　superconducting　circuits　provide　a　promising　platform　for　implementing　quantum　information　processing.　We　propose　a　non-Hermitian　magnon-circuit-QED　hybrid　model　consisting　of　two　cavities　and　an　yttrium　iron　garnet　(YIG)　sphere　placed　in　one　of　the　cavities.　Abundant　exceptional　points　(EPs),　parity-time　(PT)-symmetry　phases,　and　PT-symmetry　broken　phases　are　investigated　in　the　parameter　space.　Tripartite　high-dimensional　entangled　states　can　be　generated　steadily　among　modes　of　the　magnon　and　photons　in　PT-symmetry　broken　phases,　corresponding　to　which　the　stable　quantum　coherence　exists.　Results　show　that　the　tripartite　high-dimensional　entangled　state　is　robust　against　the　dissipation　of　hybrid　system,　independent　of　a　certain　initial　state,　and　insensitive　to　the　fluctuation　of　magnon-photon　coupling.　Further,　we　propose　to　simulate　the　hybrid　model　with　an　equivalent　LCR　circuit.　This　paper　may　provide　prospects　for　realizing　multipartite　high-dimensional　entangled　states　in　the　magnon-circuit-QED　hybrid　system.