There is no particular order which is "correct" for adverbs that modify verbs. For example, that example sentence can just as easily (and correctly) be rewritten as "She secretly often meets him in the evening at a bar," with exactly the same sense as the example.
While there are in fact some strict rules for adverb placement (adverbs modifying adjectives or other adverbs must immediately precede them, interrogative adverbs introduce the clause, relative adverbs connect clauses, etc.), adverbs which modify verbs may be placed anywhere in the sentence where they make sense and clearly modify the verb. e.g.
"I nightly read a book to tire my eyes."
"Nightly I read a book to tire my eyes."
"I read a book to tire my eyes nightly."
"I read a book nightly to tire my eyes."
"I have nightly read a book to tire my eyes"
You may prefer one or the other stylistically, but they are all correct syntactically and in all cases it is clear what the adverb is modifying.