Is there anything we can do to encourage white dating in these conditions?

Yes. You can host pool parties, BBQ's, card games, mixers, etc. These don't have to be exclusively 'white nationalist' events but you can curate the invitees and ensure that everyone in the group is explicitly or implicitily pro white. When you do that people naturally clique and share redpills among eachother. In fact they can get quite radical from a moderate position by just being in a 'safe space' (to borrow a term from the left). In this case though they are in a safe space for truth not delusions.

One of the most important things I've ever heard explained in the alt right came from Frame Games Radio. He was doing a stream with someone and off the cuff mentioned that the real way to start a revolution is to be a dick at parties. In other words if you're hosting a party or at an event with a lot of people you know well and someone in the group says something that's anti white you need to pressure them to explain themselves/reverse themselves. You might even need to ask them to leave (although just making them uncomfortable will be enough for most white people to go through a serious self reflection phase; whites are heavily attuned to social shame).

This is how we effect real grassroots political change. It's how the american revolution started (in bars and farms and homes) it's how the natsocs got started (in bier halls, farms and homes) and it's how our revolution will started (in forums, and small gatherings and gaming events, etc). There's no coincidence that part of the covid restrictions shut down bars and gyms. They don't want us gathering to talk about the man behind the curtain that has exposed himself. They know we know. Now it's just a race to see who can polarize the most people. Because the truth is polarizing. The truth itself radicalizes.

To circle back around to your question. Once you have those core groups of high trust whites meeting frequently and hanging out women will feel comfy and start showing up more, dating and marrying. Women absolutely love to feel like that are part of something and they love to feel like an entire group supports them. They will very quickly pick up on the pro white tone of your little group and they will amplify it ten fold. In fact you might have to teach the women in your group to tone it down to protect their jobs/careers as well as group opsec. Women are impulsive revolutionaries and hedonists at heart. God and men must shape them into the moral wives and mothers they must become to bare the next generation. That shaping process has been hijacked as a tool of terrorism against white people. We take it back one small social group at a time.

I'm going to be honest here. I think that Jews have outclassed us in the subtle social group curation game for at least 60 years but it's not a weapon exclusive to any one ethnic cohort. We are all capable of coalescing around a new political idea and we are especially capable of coalescing around our race. In fact the biggest problem the alt right has now isn't waking people up it's giving people a healthy social group and something to do with their new found racial consciousness. I was especially disappointed that there were very few outlets when I was waking up. Hopefully this is something we can address soon.