ROTH IRA transfer to another brokerage firm that doesn't have the same proprietary accounts

Would like to transfer all funds I have in my current ROTH IRA with capital group, to Vanguard, in an effort to consolidate accounts, and also lower the fees on the ROTH.  Capital Group's expense ratios are more than double, almost triple what vanguard charges. 

I understand you can do a direct transfer, trustee to trustee, without any tax implications. HOWEVER, my problem is such that the account at Capital Group has all funds tied up in proprietary funds there, that aren't available at Vanguard. I've read that I can't then do a direct transfer b/c the funds don't line up? I've researched and it appears that the only way to move the funds to 'liquidate' them and transfer the cash to new vanguard account? Assuming that this triggers paying taxes, etc... ? Looking for advice on how to move the funds w/o a tax penalty...