Can an electrolytic capacitor withstand 0.1 V reverse polarity?

"Can an electrolytic capacitor withstand 0.1V reverse polarity?"

If you query e.g. technical documents of a well known manufacturer like vishay:

Reverse Voltage UrevA reverse polarity of up to 1.5 V is permissible.

https://www.vishay.com/docs/25001/alucapsintroroederstein.pdf

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Edit: German Wikipedia states, a reverse voltage should not be applied for longer times (constantly), also not in case of AC voltage. negative voltages cause a current flow which due thermal spots might damage the oxid layer (with short circuit as a result.)

given the OP's question is still a factor 10 or more away from the mentioned max values, I still would consider it OK - also there is a 100k resistance so current should be limited.

Yes, aluminum electrolytic capacitors (which is the kind you have) are fine with a bit of reverse voltage. A fraction of a volt is definitely not a problem.

Edit to incorporate comment: Aluminum electrolytic capacitors are made with two aluminum plates with a conductive liquid electrolyte (and a separator) between them. The actual dielectric is a thin Al2O3 oxide layer on the etched (to increase surface area) aluminum surface.

There is a layer of that oxide on both sides of the plates. It's thinner on one side (cathode) than the other (anode) on a polarized aluminum electrolytic capacitor, but still there. It's good for at least 1V, so an ordinary diode is adequate to protect the capacitor. It's robust because small defects get anodized away (since the cathode becomes the anode). Bipolar caps have roughly equal thickness layers of oxide, so less capacitance per unit volume.