This doesn't seem to be related to Pi-hole:
Pi-hole isn't involved in routing at all.
You'd have to figure whether and how Tailscale would allow to configure a custom DNS server for its clients, e.g. whether the machine hosting Pi-hole has to become a Tailscale client as well, or whether the Tailscale gateway (if there is such a thing) would be able to route DNS traffic accordingly.
You should consider to also consult Tailscale's documentation and support channels.
Wireguard has no ties to Pi-hole neither.
You may have a look at our configuration examples for Wireguard, but there's absolutely no guarantee that they are going to work with Tailscale.
You could approach the Wireguard folks as well, but I think they'd also refer you Tailscale, as only Tailscale would know what they've wrapped around Wireguard to make it their own product.