Yes, the tanker belongs to "Restricted in Ability to Maneuver", which means they have priority over pretty much anything. You can't ask them or expect them to detour to avoid you, you must avoid them.
In open water, large vessels like that give way to smaller vessels when appropriate all the time.
https://www.navcen.uscg.gov/?pageName=def3g_RAM https://www.navcen.uscg.gov/?pageName=def3h_CBD