This question sounds familiar...
You will normally ovulate between days 11 and 16 of your cycle. Day 1 is when your period starts. Sperm can survive up to about 5 days. No app can tell when you ovulated - it's a computer program estimate. You can't determine ovulation "after the fact."
You had sex on day 7 with Guy A. It's early but possible.
You had sex on day 11 with Guy B. Likely just before your peak fertility.
The withdrawal method is very unreliable. Especially when having sex multiple times.
Dates are based on your LMP. From May 4 to July 1 is 8 weeks and 3 days. The dates do not indicate when you became pregnant. It takes several days from when you had sex until the ovum implants.
I'd say Guy B is the most likely but it could be either. You will need that DNA test.
Hope it helps.