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(Nd,Tb,Sr)₃Fe₂O₇ crystals, n=2 Ruddlesden-Popper ferrite, exhibit dense networks of topological defects (eight-state vortex-antivortex pairs), associated with four oxygen octahedral tilts at domains and another four different oxygen octahedral tilts at domain walls. Here, utilizing dark-field transmission electron microscopy (TEM), we show experimentally that the formation of eight-state vortex domains follows a universal behavior captured within the Kibble-Zurek scaling mechanism. In addition, a self-strain-induced fragmentation of such vortex domains occurs when long-range ferroelastic couplings become dominant. We develop a complete picture of the topological defect evolution through 1^st-order and 2^nd-order phase transitions, affecting significantly the condensation of topological defect types. How the resulting microscopic domain structures influence macroscopically phenomena will also be discussed.