Maybe they see manned turrets as simpler / less expensive?

They are simpler and less expensive.

Not every military is convinced on the viability of unmanned turrets.

If the advantages are not (fully) applicable to a given use it makes little sense to spend the adiitional resources an advantages of a manned turret.

Also, you may have better situational awareness in a manned turret. 

This is a common criticism of unmanned turrets.

Which may or may not be valid. Current experience by users indicates that its not valid. Of course this depends on several variables. For example how the turret and the crew stations are equiped. Which in turn has direct influence on cost.

Although looking at the Czech tender Unmanned turret, and many other unmanned turrets its seems they are actually higher than the manned turrets. and have additionally higher hull roof to accommodate crew under it

The height of a turret any hull depend on the desired characteristics and resulting design.

If the turret is not supposed to have a significant Intrusion into the hull, eg. no turret basket, it has to be higher if a large gun elevation is desired from a conventional gun mounting.

The deterimning factor for hull hight usually is not where the turret crew is situated but its about the required ergonomics and protection level.

Never the less vehicle height is of rather low relevance nowadays. As long as the railway transport dimension limits are met there are few constrains.

It seems no other IFV met Czech Rail transport standard dimensions , And as far as i understand the unmanned turrets also had issues with armoring as most were not capable of matching the vehicle armoring even in max up-armored versions. The turret on the pics was a Kongsberg MCT30 that is only Level 1 protected and can't be up-armored to match the protection levels of the vehicle which was one of the Czech requrements..

The Czech decision to buy the CV90 has online one reason: money.

The CV90 is the cheapest solution and the manufacturer made the required concessions for local production and involvement of the local industry.

The bidding and the program was formally stopped last year not for technical reasons but because the required documentation and/or above mentioned local involvement requirements have not been met by either bidder. Because of this no bid was concidered acceptable. The decision to buy the CV90 now was made as a government business decision.

P.S.: There is a NATO standard for rail transport and all contestants meet it. Demounting secondary armament and external armor and skirts is acceptable and pretty common.

I can imagine cost was a major factor, ,Slovak tender where CV90 also won supposedly had the following bids. 

One of the remarks vs the unmanned turret was that it can't be operated without power while a maned one can still be operated and fired under manual power? *Altough i would imagine Puma turret with glass optical channels could probably be operated manually if someone ordered it as such.

  152 vehicles,  110 infantry fighting vehicles, 15 command vehicles, 9 reconnaissance vehicles, 3 armored personnel carriers, 9 self-propelled 120-mm mortars, 3 engineering vehicles , 3 ARVs

Total procurement costs of the offered vehicles including VAT and infrastructure costs

* we are paying more for Boxer through OCCAR than either Czech or Slovak CV90MK4 cost

https://below-the-turret-ring.com/armored-vehicles/slovakia-announces-the-cv90-mk-iv-as-its-preferred-ifv/

Mr. T (MrT4) said:

One of the remarks vs the unmanned turret was that it can't be operated without power while a maned one can still be operated and fired under manual power? *Altough i would imagine Puma turret with glass optical channels could probably be operated manually if someone ordered it as such.

Extremly unlikely. It at the very least would require a major redesign.
Basically no modern all electric turret can be operated without power. Usually if redundancy behond the engine, APU and on bord power storage is required the solution is to add additional storage.
Operating the turret manually is de facto an outdated concept. Even if it is possible power loss is a mission kill and demands immediate disengage and fall back.

Mr. T (MrT4) said:

I can imagine cost was a major factor

Usually it allmost the only factor that counts. Neither the Slovaks nor the Czech really bothere testing. They just read trough the documentation and compared them. The entire Slovak test program of the provided test vehicles took them five days. The Czech have not been much better. Under this condition a sensible comparison of technical details isn't possible. Which means the decision can only be made based on numbers on paper.