To my knowledge, you can roll. You can liquidate and pay the tax or take out the required amount each year as required.
I guess it would depend upon the age of the beneficiary. If you inherited and wanted to take some out... isn't there's a required distribution schedule?. I suppose you could take that amount without paying premature distribution tax if under 59 1/2. (If beneficiary took out more than the "scheduled" amount, would 10% premature distribution tax apply to the amount above the required amount?) If beneficiary is >59 1/2, doesn't seem to be any benefit to keep the account separate.
Only a spouse's IRA can be rolled into a personal IRA. For non-spousal inherited IRAs the timing of distributions is very different from a regular IRA. You have to start taking distributions after the first year, spread out over your expected lifespan.
It's a non-spousal inherited IRA, so it can't be rolled into one's own. But it can be stretched for the lifetime of the beneficiary, with RMDs commencing immediately.