Until somebody who knows more shows up: 'humilem hanc domum' is 'this humble house', in the accusative case (direct object). 'exaltant' is exalt, third person plural, thus 'they exalt this humble house'. 'undequaque' seems an odd word. My best guess is that it means 'from everywhere'. This is Church Latin, not classical Latin. Thus, finally, 'People everywhere exalt this humble [irony alert!] house.'