Help combining pumpkin pie and sesame filling

Hi all!

I am working through a dessert recipe that I'd like some advice on before I ruin several batches while experimenting. I want to make a pumpkin pie, but then drop in bits of sesame filling. I think those flavours would go really nicely together.

I'm worried about the sesame drying out too early though. I'm looking at the filling from this recipe: Marbled Black Sesame Shokupan https://share.google/Y8YSRWapk8azxMasQ

But normally the sesame paste is enclosed in the bread dough. In my idea it would be exposed to the direct heat of the oven. Any ideas on how to keep it from drying out? I was thinking of adding an egg yolk or two and maybe making it a bit closer to a custard than a paste.

Any advice? Anyone who's made something similar?