I think that you need to let your dp decide this for themselves. I'd expect them to keep their decision as "subject to change" right up ubtil they were due to have to leave for the event.
Losing a parent is devastating, and funerals are for the living left behind to help process this loss. For me, it would depend on whether my Mum/siblings would need me there to get through the day.
On the other hand, I'd want you to be in good health with no pregnancy related issues, and to be set up with food etc for me to be able to go away for a couple of days.
I'd want to make sure that you had a written birth plan that your midwife has a copy of, a bag packed, and that everything was ready for baby. Ideally you'd be on maternity leave and I'd be video calling for regular check ins. You'd just need to rest and relax.
I'd also want someone who can step up as birth partner should that be required (even a doula), and would want details on every flight back that I could possibly book in an emergency.
I'm so sorry that you and your partner are having to deal with this at this time.
And I have to say that it sucks that in 2025 you feel like you need to hide your sexuality to post about a topic. The world needs to do better.