If you sent a message to the PM already on the profile, requesting the name be changed and have not gotten a reply, you should review the Unresponsive Profile Managers process which includes sending 3 different types of messages, one of which you have already done. If you do not hear back in a week, then you would fill out the form so Admin can try to contact them. If they don't respond to them, then the profile that you are asking about will be orphaned and you will be notified. Then, you can adopt it and change the name on the profile so it is correct.
I agree that having the correct LNAB on a profile is very important to make sure that the correct ancestors will be included. The marriage source is important because that does match the Find a Grave, but it has both of their names together. Possibly, you can find other sources, using something on the marriage source.