From the Rosen-Zeitung 1887, page 26:

Die Entstehungsgeschichte der Polyantha-Rosen.

Durch Vermittlung des Herrn Wilhelm Kölle in Augsburg kommen wir in Besitz einiger Originalbeschreibungen, wie solche von der französischen Züchtern mitgeteilt wurden, welche nach der Uebersetzung wie folgt lauten:
...

2) Herr E. Dubreuil , Rosiériste à Monplaisir-Lyon schreibt:
"Die Perle d'or stammt von der einfach weiss blühenden Rosa Polyantha durch ein danebenstehendes starkes Exemplar der Madame Charles, natürlich befrüchtet, die, wie ich vermute, der Perle d'or ihr Kolorit verleihen hat."

My translation:

The History of the Development of the Polyantha Roses.

By arrangement with Mr Wilhelm Kölle of Augsburg, we have received in our possession some original descriptions, as were given by the French breeders, the translation of which reads as follows:

2) Mr. E. Dubreuil, rosarian of Monplaisir-Lyon writes:
"Perle d'or comes from the single white flowering Rosa Polyantha by way of a strong specimen of Madame Charles growing alongside it, naturally fertilised, which, I presume, has given Perle d'or its colouring."

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The other references here give Mme. Falcot as a parent. This seems authentic because it was from Dubreuil in 1887. The original text in Rosen-Zeitung does give Dubreuil's initial as 'E'. To me, it isn't entirely clear from the text whether the seed parent is Mme Charles or R polyantha. I've tried to translate Dubreuil's description as literally as I can. I found it rather interesting. The other roses mentioned in the article are 'Paquerette', 'Mignonnette', 'Gloire des Polyanthas' and 'Miniature'.