Nygren rhymes with:
ahlgren, almgren, berggren, bergren, blomgren, cedergren, edgren, elvgren, forsgren, halgren, hallgren, helgren, holmgren, hultgren, lagergren, landgren, liljegren, lindgren, lofgren, lovgren, lundgren, lungren, malmgren, mellgren, nordgren, ogren, ostergren, palmgren, rosengren, sandgren, seagren, shogren, sodergren, stromgren, westergren, youngren
Nygren sounds like:
nagorno, najarian, nanogram, nazarian, negrin, negron, negroni, newsroom, nigerian