Can you buy Mouse ears here and have embroidered?

Yes.

I called and was told Only Inside parks

Yes you can. I bought some last week at World of Disney and had them embroidered. Two options for font just ask someone for help.

With World of Disney having half of the store closed I don't think you can get this done there

Go to the "world of disney" store. They'll help you out. I know they definitely sell mouse ears there, there's a huge wall.

Nope

Yed