`execute at` is not compatible with `execute positioned` on Realms

Summary:
Typing execute at together with positioned works on single player, but not on Realms

Verification Build:
1.19.81

Regression Builds:
N/A

Impact:
This has broken our content during development after we have started testing on Realms

Repro Steps:
1. Open single player world
2. Type /summon armor_stand ~ ~ ~
3. Type /execute at @e[type=armor_stand] positioned ~ ~5 ~ run setblock ~ ~ ~ coal_block
4. Coal block appears 4 blocks above armor stand

5. Join Realms world
6. Type /summon armor_stand ~ ~ ~
7. Type /execute at @e[type=armor_stand] positioned ~ ~5 ~ run setblock ~ ~ ~ coal_block
8. Chat spits error

Observed Results:
Single player places a block. Realms sends an error.

Expected Results:
Both single and Realms should have the same result