This question is extremely confusing given in your other post, you were the one who experienced a condom slip and were on PEP, and now it's your partner who is also male, and he experienced a condom slip around the same time and also took PEP?
1) Test can be taken 30 days after finishing PEP - whenever the last course of PEP was taken, regardless of when the exposure was.
2) No idea. Talk to a counselor about managing stress.
3) I'm not able to explain the behavior of the entire population of people who have taken PEP. Statistics don't lie, and PEP is highly effective.
A duo only has a 4 week window so the first time exposure was safe. 12 weeks is a very outdated guideline but some docs still use it for no valid reason.
You have to wait 4 weeks past the last PEP before you can test with a duo for risk #2.
An anecdotal account of someone else's experience does not have anything to do with another person't situation. Getting HIV is a matter of bad luck and is not predictable except from the test result so the only thing to do is try to relax until the test can be done.