Nah, hotaru has much more hitstun on CH than Tsubaki's DPs, and C DP has no invuln in EX. D DP is only marginally better than A DP, it has 1, one more invulnerable frame.
The A DP only has 9 frames of invuln and goes active on 10. Hotaru has 14 frames of invuln and goes active on 11 or something.
The hotaru is not going to be used meaty very often, if you want to beat someone's dp on wakeup you try to use your invulnerable move as late as possible without exposing yourself to a 5a. so in order for tsubaki's dp to beat hotaru, you're likely going to have to use it 10 frames or so after waking up. if you're trying to use it to beat anything other than hotaru you're toast. if he tries to use hotaru, most likely he's on top of you. Even if you get a CH you have zero combo potential in EX. you get 600 damage if you time it just right to call it out. but more than likely you're going to eat 3-4k damage. With that kind of option you are better off calling it out by blocking and trying to DP after the hotaru, I think.
It wouldn't seem to be quite the same in CP because tsubaki's DP is better, but hotaru is 1-17 invuln then too so I'm sure it will again be beating it, BUT quite possibly not the D Dp anymore.
But you can crouch hotaru in CP so there's that, but then tsubaki comes for 2800 damage + combo after