Life insurance

I need advice… my dad unfortunately passed away April 4th this year, and almost 2 years before that I lost my mom.
My dad had a 30k life insurance and listed my sister as beneficiary and me as co beneficiary.
The insurance should have been paid out by now since the funeral home had received their check from them. I called the life insurance but they wouldn’t tell me anything as co beneficiary. I called back today and pretended to be my sister and gave information to prove identity… wrong I know… I asked about the 26k (what was left after funeral home costs) and they said it was sent and cashed already.
I hung up and texted my sister saying what the life insurance told me. She responded shocked and said she’d call them.
She supposedly calls them and gets a totally different answer. Something about money sent to pay on my dads rv and about the amount sent to funeral home but that they claim the remaining amount hasn’t been sent or cashed yet.
But I find it so hard to believe because the told me something 100% different.
I want to believe her. It’s not about the money but about being lied to about something so major.
She claims she only just got her taxes back and that’s how she put a down payment on a house and has gotten all these things.
I just have no idea what to believe. I’m not going to fight over money. If she kept it whatever. I care about being lied to and when confronted creating an even bigger lie.
I want to believe she’d never do that to me and our brother. But she’s been sketchy with money before. Which honestly makes me question my dad’s choice of beneficiary because he’d always want things equal between the 3 of us. He loved us all equally.
When he was alive and sold his house he gave each of us an equal cut of that to help us out.
There’s no watched intend for her to keep it all.
Idk. I need someone to tell me I’m just being impatient, and that it’s not as sketchy as it seems.
I want to believe my sister and I want to keep our good relationship.
But I don’t want a relationship with someone who’d do that to family….
What do I do?