The Occultum Recruitment Letter

Preface: Hi guys! I have posted on this subreddit before, but this is my first Apocrypha. I am planning on doing a series around the Occultum, as long as you guys don't hate it! There will be secret documents, letters, and recorded interviews. Please give me feedback! Advice, questions, constructive criticism, are appreciated! Thanks! Also, there is a lot of latin words in this and a cipher is used. It is a real cipher that you can find a translator for. I like to call it the "Reman Cipher", see if you can figure it out.

Dear Recruit,

Welcome to the Occultum! We are a secret Imperial society that has formed in the wake of the Soulburst, the Alliance war, and the great evil of Bal that has invaded this land. We are here to carry on the Imperial way of life through these dark ages and onto the day that the Legion rises once again. I must make one thing very clear. We are not involved with the current Empire. They have betrayed us and our beliefs. They have given themselves up to the Worm King and Bal, and are now considered traitors and scoundrels. You are a spy. We will send on you on missions all across Tamriel to document this war and report back. After the interregnum has ended, we will have archives full of accounts of this dark time. On the Sundas after you receive this letter, report to the Abscondito located in [Wkh dedqgrqhg krxvh lq wkh zdwhuiurqw] the code word is [Ohppdwh].

Signed, The Explorator Lux

PS: Put this letter in your hearth. It is enchanted and will soon burst into flames.