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Two-colour polarization labeling experiments have been used to explore the excitation spectrum of the rubidium dimer in the region 25500 - 27000 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$, aiming to establish the symmetry of excited states observed by Han and Heaven {J. Han, M. Heaven, J. Mol. Sprectrosc. 268, 37-41 (2011)} in earlier work. The spectra we recorded in fact probe quite different electronic states; we identify them from $ab initio$ calculations as the 5~$\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Sigma u+$ and 5~$\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Pi u$ states, dissociating to Rb 5s + Rb 5d atoms. The home-made pulsed laser used to label levels in the electronic ground state, with nominal linewidth of 0.3 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$, is not sufficiently selective for this heavy-alkali species. The spectra are a tangled confusion of short and rather irregular progressions of P,R doublets and/or Q lines. We have had to use cross-correlation techniques to identify transitions seen in different spectra that share a common ground state level, to establish assignments. Analysis confirms unusual vibrational patterns in the lowest vibrational levels, from avoided crossings with ion pair states.