Yoma 38 Ingredients of the Ketores

The Gemora relates that there was a family named Avtinas that knew how to make the ketores but they didnt want to teach anyone else. Experts were brought in without success. Avtinas knew how to make it that it would be מעלה עשן - the smoke would rise in a column and the experts from Mitzrayim could not duplicate this. Rashi says they didn't know which עשב (herb, grass) was the correct one. The Beis Yosef (133) learns from here that even if this particular ingredient is missing, the ketores is still good. The Mishna L'melech and others are bewildered that the Beis Yosef is against a later Gemorah that states explicitly that if this ingredient is missing, there is a chiyuv misah? מהריץ חיות answers that there will not be a chiyuv if the ingredient is not available. Tosfos Yeshonim explains our Gemora by saying that they had an ingredient which was called מעלה עשן and therefore it was כשר, however it was not the one that could produce the smoke in the correct way. Rav Elozar Landau notes that they had the correct one, but they couldn't ascertain which was the best quality for the correct result.