hanging 6ft 45kg muay thai bag on ceiling

[Lester08T]

any thoughts about joiner who admits haven't hung a punch bag nevermind a 6ft 45kg muay thai bag, but he said he is 150% sure it is safe but he doesn't know that i do kick harder than average. he said he has screwed that long plank of wood ~2.5m long, 6" wide and 2" deep , he used ~5.5" screws with washers into 5 ceiling joists, the last set of 2 screws are not in joist he said. He guessed where the joists were by cutting a ~3cm wide 15cm long slit into the thin ceiling and taking a look inside, then used his electric screw to put the plank up.
I plan to have two bags up, one on lhs and other rhs. l messaged my old muay thai master and he said, 'Nope not secure for 1 45kg bag, needs to be bolts not screws. That won’t last a day' what are your thoughts, bolts OR screws with washer? because ceiling is quite high, l have bought 10mm static climbing rope to hang it, with the rope going through the metal rings on the 4 straps attached to top of bag at least twice, the bag hasn't been put up yet. while waiting for the rope to arrive, l could just attach my TRX straps to the swiveling hanger which is bolted on, and swing on TRX on hanger and see if it is stable. l am 65kg, could swing on it with joiner so ~135kg? is this a worthwhile experiment to know if it will be safe in the long term (~5 years) or even a day? opinions appreciated especially from those who have knowledge on this. thanks

[reddbod]

Should use rawl anchor bolts just to be safe for heavy bag

[ArrynField]

How about using exploding anchor bolts?