Questions about Kyushu bus

Hello

I greatly appreciate any helps with regards to the following questions;

I have booked bus tickets for the following trips;

- Fukuoka to Yufuin departing from Hakata Bus Terminal - Is the bus terminal right outside of Hakata JR station?
- Kumamoto to Kagoshima departing from JR Kumamoto ekimae (as per Kyushu highway bus reservation site) - Is the bus station just right outside of JR Kumamoto station? I am especially confused with the location of Kumamoto bus station because searching on google maps gives me the following address which is quite far from the JR Kumamoto station

Kumamoto Transportation Center temporary bus terminal
熊本交通センター仮バスターミナル

https://kyushubusbooking.com/highway-bus/kirishima-go/

- Is Beppu bus station for bus from Beppu to Kuju (Chojabaru visitor centre) right outside of JR Beppu station?

Also i will take the following separate bus rides between Beppu and Aso;

- Yufuin to Beppu
- Beppu to Kuju (Chojabaru visitor centre)
- Chojabaru visitor centre to Kurokawa onsen
- Kurokawa onsen to Aso JR station

May i please ask if there are any other bus companies that run the above routes (that do not require prior reservations) besides the Kyushu Odan bus?

Thank you so much in advance for everyone's help!