It can help if you are eating the exact same food at the same time so he can see you eating it. Even take a piece of his bite a piece off, make a 'yum' sound and offering it back (without forcing the issue). I found with DS (BLW from 5.5 months so it was all finger food from day 1) that he has phases of being unsure about what he is offered as though maybe it isn't edible. I act like the king's jester and test it for poison to show him it is good food and then he tries it. I have always eaten the same things he is offered and notice he inspects my plate to be sure we have the same, again it is like he is checking it is edible.
Otherwise, I would ignore anything that makes it to the floor and don't clear up until after the meal (or it will become a drop pick up game) and try to intercept the dropping by catching his hand or the food and thanking him for 'clearing up'. Offer the same food a few days or a week later and he might one day try it (or if he shows an interest in what you are eating later in the meal offer a piece from your plate).
I always make meals that include something I know DS likes alongside new foods that he may or may not try the first time he sees them.
No advice for the suction mat, I stopped using ours after a few weeks and moved to a plate instead (non suction). With a plate I could remove ALL the food in one go if dropping became an issue, then just offer one piece at a time from the plate and again use the plate to 'catch' anything before it is dropped...this way you get to praise desirable behaviour of clearing up rather than have to deal with the undesirable behaviour of dropping iyswim.
hope something there might be helpful.
