To invite or not to invite

I would call her directly and stress to her the importance of her being there for you but that if she can’t make it you completely understand, but due to COVID you have to stick to the number you're allowed. So, if she’s not able to come to let you know now.

I would speak to her directly and let her know your concern & take it from there

I think Rebelle Fleur said it perfectly!! Invite her but also speak to her directly to stress the importance of an accurate RSVP!

I would go ahead and send her the invite and then regularly check in with her to make sure she received it and find out her exact plans. If she says she's coming, tell her that's great, and then drop hints to help solidify her decision. If she's traveling, give her hotel recommendations and, if need be, let her know about good flight prices. Basically, I say drop every hint you possibly can, and also add how much you can't wait to see her, anything that burns into her brain that she's wanted and expected there. Good luck!