You will probably be introduced to the examiner by .....

You will probably be introduced to the examiner by his/her surname
This sentence has the meaning of :
You will be introduced to the examiner, and the one introducing you to the examiner may tell you their surname only, like – this is Mr. Wong.
u will be introduced 唔係解你會被介紹咩 – yes


成句好似好怪 – The sentence is a bit strange, but the meaning is very clear, you cannot find any other explanation of this sentence.
I do not think this sentence is wrong in sentence structure, only that the meaning is a little strange.

１．對，You will be introduced = 你會被介紹
２．對，成句好似好怪咁的。點解？
先譯大半：
You will probably be introduced to the examiner
你可能會被介紹給考官認識
呢度都冇問題，問題在於 by his/her surname。
例如：Tim was introduced by his English name.
用主動句譯成中文：（某人）以 Tim 的英文名作介紹向人們介紹他。
睇返原句：You will probably be introduced to the examiner by his/her surname
用主動句譯成中文即係：（某人）可能會以考官的姓氏，將你介紹給考官認識。
將你介紹俾人，但係用考官個姓？根本不合邏輯。要糾正好簡單，視乎原本句意：
１．將 by his/her surname 變成 by your surname。
２．將 you 同 the examiner 互換位置。