Based on the size of the follicles two months ago which was a little over a quarter there was no longer a need for her to be paired so for her to refuse a male is pretty normal (animals often know best)
Now by this time your follicles are either golf ball size or are now eggs so they would become harder to palpate.
Have you witness an ovulation? Where is she currently located in her tub (cool side or warm side?)
I have not seen what i can for sure say is an ovulation. She swelled up like she ate a football but wasnt rock hard and no obvious tail suck. But i have been told the bigger they are sonetimes hard to see. She is still mostly on cool but has gone to hot side too.
It can be difficult to tell with larger females. I find that bigger females often have longer building/ovulation phases as well. I have a huge 17 year old girl that I swear looked like she was ovulating for 3 days.
It can be less defined for large females too. Usually you’ll mistake the build for OV a few times but when you finally see it you’ll know. Look for that tail suck…
I bet if that female hasn’t ovulated then she will soon. Looks like a good build to me. I’d keep an eye out for an OV and shed then you’ll be good to go.