Don't sell the goat

I don't usually cover Aramaic דקדוק and I cannot claim to know terribly much about it but it seems the entire world sings חד גדיא pronounced thusly: חד גדיא, חד גדיא דְזַבִּין אבא בתרי זוזי It's a tricky word because almost the same word is used for buying as for selling. However, it seems from the הגדות מדויקות that the proper pronunciation is in fact דִזְבַן. I haven't done too much research on this but I know someone who has. The Haggada of Rabbi Jonathan Sacks by Koren Publishers also has דִזְבַן.

הגיענו - הגדה vs יגיענו

כן ה' אלוקינו יגיענו למועדים ולרגלים אחרים

In just about all the הגדות I've seen, the נוסח of the ברכה at the end of מגיד is as above. However, in אבודרהם and רבינו סעדיה, as well as the הגדות מדויקות you will find the word יגיענו substituted with הגיענו. This version seems more correct considering the context. The entire ברכה is in the second person. Why would we change to the third person with יגיענו? Furthermore, it seems this portion of the ברכה is meant as a request. The word הגיענו is certainly לשון בקשה whereas the word יגיענו seems to be merely a statement of fact. Why is it that almost all הגדות have this version?