So apparently there are a bunch of bug fixes coming, but DLSite takes a while to upload game updates.
In the meantime, if you really want to get past that bug there is a hot fix you can do with some elbow grease.
You will need Bioreube's
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. You might also need the KiriKiri executable, I've attached it down below.
Extract data.xp3, then rename data.xp3 to something else, or delete it if you like to live dangerously.
In data>system2 find 拠点.ks. You need to edit line 126 from "[eval exp="tf.i = getNextEvolutionHeroineID(tf.i)"]" to "[eval exp="tf.i = -1"]. This will disable Heroine Evolution, allowing you to bypass the event.
If my first draft of the MTL is done before peperoncino's bug fix goes live it's quite likely I'll ship the draft with evolution disabled. Especially knowing that a fix is on the way I don't particularly want to take the time to debug the actual problem myself.