Anyone flown MS788 MUC-CAI and/or MS995 CAI-YYZ in business?

Lie flat seats?

Certainly not on the MUC sectors. It's (usually) a B737 with a dedicated 2-2 business-class cabin. Comfortable enough.

What to expect for vegetarian food?

Can't help. But regular meals are good quality, generous with healthy salads. It's a large international airline so I imagine they are used to catering for vegetarians.

They are dry, some FTers report BYOB, any advice of what is tolerated by the crew (ie: at MUC and CAI airports, should I buy a bottle of Vodka, or a bottle of wine, or little bottles? and just mix my own drinks at my seat)?

May be hard to believe, but some passengers choose the airline because it is an alcohol-free environment. Alcohol isn't banned in Egypt, but the airline policy is to promote itself as a dry carrier. It's not a petty rule to be circumvented. Consuming alcohol may be offensive to your neighbour. If you really can't survive the flight without a drink, you might carry a miniature (think hotel mini-bar) to top up your coke discreetly.

Assumptions: No PJs. Poor IFE.

Correct!