If the Bible Code is dependent on letters (which is how I understand it), then the language it is written in does make a difference, simply because you'll get different letters at different points in the text.
If it's dependent on words, it will still depend on the syntax of the language - yes, English tends to have a more similar sentence structure to the Germanic languages, but different from, say, Welsh (prime example is that in Welsh, the adjectives come after the noun they describe).
Getting the same coherent messages in several languages in the same area would be an astronomically improbable occurrence.
Regarding the whole "Old English/Middle English" thing - I've read Chaucer and Shakespeare, and seen a copy of Beowulf. Old English is a completely different beastie, even with a different alphabet - there's a character that looks like a lowercase d with the top half bent left and a cross mark through the top that corresponds to 'th' as an example that I recall. Most people who see it don't even recognize it as a relative of English, which explains the confusion: for them, the 'oldest' English is Chaucer/Shakespeare.
-Not a linguist, only a linguaphile.