Have you had a look at the roots? I lost a Burr 'Nelly Isler' not long ago, only a few months after buying it. The bulbs were just as shriveled as on yours and kept on blooming with no problems. I unpotted, and all the roots had rotted due to a big wad of sphag around the roots, hidden deep in the bark so I didn't see it!!
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(So now I will follow advice I got here on OB
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: Repot immediately upon purchase, even if there are flowers! It avoids nasty surprised later on)
Really nice flowers by the way. I especially like the orange one!