Responsa for Nedarim 66:5

רבא לא אמר כרב הושעיא דקא מוקים לה למתניתין כדברי הכל רב הושעיא לא אמר כרבא גזירה שלא ליפרע משום ליפרע

disputed this and maintained: He must swear how much he expended and is reimbursed [by the husband]. R. Dosa b. Harkinas ruled as they did; whilst R. Johanan b. Zakkai said: Hanan has ruled well — it is as though he had placed his money upon a deer's horn.<span class="x" onmousemove="('comment',' I.e., he cannot expect its return. ');">⁵</span>

Maharach Or Zarua Responsa