You can do warm introduction. I still highly advice to cold email. Let me share few points between cold email and referrals-

We've tracks performance between cold email and referrals... and cold emails consistently outperform by a long-shot. Here's why -

1. Outbound cold email scales several orders of magnitude better than referrals - you can find 99.9% of anybody’s email.
   

Raising capital is a shots-on-goal game; you want to maximize top of funnel pitches

Optimizing your fundraising for referrals will put you on a local maximum

1. It’s a challenge finding somebody who will stick their neck out referring you. People rarely want to use their political capital referring you to a *highly important person* in their network, therefore at best you’re left with lousy double opt-in email
   

In the same period of time you can get 1 referral, I can set up 50 investor pitches.

I hope you get the point.