Thank you for your replies
Mamillia seems to be a good / acceptable hotel in Jerusalem and my Parents are willing to go there, so that's great, first problem solved

Tel Aviv : Dan . They were walked 30 years ago despite they reconfirmed their stay during a previous stay 2 weeks before. I remember something like "walking" from one hotel to another, it was cool )
The main problem is there is no agreement on this hotel between my parents

Thank you for letting me know about the lack of balcony at the Dan
Hilton seems to be acceptable and they have balconies ? (according to the picture they do)
maybe there is a separate thread for this hotel ? ; not sure how far diamond HH will go there
More important : my BOTH parents are willing to go there (second problem on the way of being solved )

Hard to give recommendation when you don't know anything about the country , thank you again all for your advices