たしかに (translations)→ actual actually admit admittedly definitely despite distinctly do evidently exactly forsooth goddam indeed maybe namely obviously question realize really still strictly sure true very well yes
まぎれもない (translations)→ absolute certain certainly decidedly genuine indisputably indubitably inescapable sovereign truly undoubted undoubtedly unfailing unmistakable unquestionable
まぎれもなく (translations)→ absolutely only ultimately
間違いない (translations)→ adamant correctly fait accompli know must right surely